feat(settings): 新增「站点类型」三态开关，关闭订阅后用户端收起所有「订阅」入口与文案

后台功能开关页新增「站点类型」单选：充值 & 订阅（默认，即现状）/ 仅充值 / 仅订阅。
它由两个后端开关派生并在保存时同时写回：
- subscription_enabled（新增；默认 true，缺省/空值视为开启，仅显式 false 关闭），按既有
  开关模式贯通常量、公共设置、SSR 注入载荷、默认值、更新写入、DTO、审计 diff 与前端注册表；
- payment_balance_disabled（支付配置里既有的 BALANCE_PAYMENT_DISABLED，此前只能走接口/数据库
  改），补进公共设置与注入载荷，让用户端在任何鉴权请求之前就能推导站点类型。
两者都关闭是接口层可表达但 UI 不提供的组合，前端归为「仅充值」，后台保存时会把余额充值重新打开。

「仅充值」时的表现：
- 用户侧边栏隐藏「我的订阅」，「充值/订阅」入口收窄为「充值」；管理端侧边栏隐藏「订阅管理」
  入口（页面仍可通过地址访问）；
- 购买页不再渲染「订阅」tab，只剩单个 tab 时顶部切换器随之隐藏；tab 列表变化时当前 tab
  自动收敛到可用项（关闭订阅回到充值、仅订阅站点重新打开订阅进入订阅），列表为空时展示
  「充值与订阅均暂未开放」而不是一个必定被后端拒绝的充值表单；
- /purchase 的页头标题/描述与 document.title 改走 resolveRouteMetaKeys 按站点类型切换；
- /subscriptions 路由新增 requiresSubscription 守卫，直达时重定向到仪表盘；
- 顶栏订阅进度徽章不再挂载，App.vue、PaymentView 与徽章组件都不再预加载/轮询订阅接口；
- 用量页隐藏「计费类型（余额/订阅）」筛选，Key 用量公开页「订阅类型」行改为「计费方式」。
「仅订阅」时侧边栏入口与页头显示为「订阅」，购买页只剩订阅 tab（余额下单由后端既有逻辑拒绝）。

购买订阅接口、已有订阅的计费、兑换码发放订阅与管理端订阅管理页面本身均不受影响。
featureFlags 抽出纯函数 resolveFeatureFlag，新增 utils/siteBillingMode 承载三态派生与反解，
PaymentView 测试改用响应式 store mock 覆盖开关双向切换。

backend/internal/handler/admin/setting_handler.go

@@ -383,6 +383,7 @@ func (h *SettingHandler) GetSettings(c *gin.Context) {
 		GrokDefaultBaseURLMode:         settings.GrokDefaultBaseURLMode,
 
 		AvailableChannelsEnabled: settings.AvailableChannelsEnabled,
+		SubscriptionEnabled:      settings.SubscriptionEnabled,
 
 		ModelPlazaEnabled:       settings.ModelPlazaEnabled,
 		ModelPlazaRequireAuth:   settings.ModelPlazaRequireAuth,

backend/internal/handler/admin/setting_handler_audit.go

@@ -579,6 +579,9 @@ func diffSettings(before *service.SystemSettings, after *service.SystemSettings,
 	if before.AvailableChannelsEnabled != after.AvailableChannelsEnabled {
 		changed = append(changed, "available_channels_enabled")
 	}
+	if before.SubscriptionEnabled != after.SubscriptionEnabled {
+		changed = append(changed, "subscription_enabled")
+	}
 	if before.ModelPlazaEnabled != after.ModelPlazaEnabled {
 		changed = append(changed, "model_plaza_enabled")
 	}

backend/internal/handler/admin/setting_handler_partial_payload_test.go

@@ -186,3 +186,20 @@ func TestUpdateSettingsValidatesTencentCaptchaAppIDWhenEnabledFlagIsOmitted(t *t
 	require.Equal(t, http.StatusBadRequest, rec.Code)
 	require.Contains(t, rec.Body.String(), "positive integer")
 }
+
+// subscription_enabled is an opt-out switch: an explicit false is written as-is,
+// and a later payload that omits the field keeps the stored value.
+func TestUpdateSettingsSubscriptionEnabledIsWritableAndKeptWhenOmitted(t *testing.T) {
+	h, repo := newStepUpSwitchTestHandler(t, map[string]string{
+		service.SettingKeySubscriptionEnabled: "true",
+	})
+
+	rec := doUpdateSettings(t, h, map[string]any{"subscription_enabled": false}, nil)
+	require.Equal(t, http.StatusOK, rec.Code)
+	require.Equal(t, "false", repo.values[service.SettingKeySubscriptionEnabled])
+
+	rec = doUpdateSettings(t, h, map[string]any{"site_name": "Example Gateway"}, nil)
+	require.Equal(t, http.StatusOK, rec.Code)
+	require.Equal(t, "false", repo.values[service.SettingKeySubscriptionEnabled],
+		"a payload without subscription_enabled must not flip the stored value back to true")
+}

backend/internal/handler/admin/setting_handler_update.go

@@ -344,6 +344,9 @@ type UpdateSettingsRequest struct {
 	// Available Channels feature switch (user-facing)
 	AvailableChannelsEnabled *bool `json:"available_channels_enabled"`
 
+	// Subscription feature switch (user-facing subscription surface; see SettingKeySubscriptionEnabled)
+	SubscriptionEnabled *bool `json:"subscription_enabled"`
+
 	// Model Plaza feature switches + description
 	ModelPlazaEnabled     *bool   `json:"model_plaza_enabled"`
 	ModelPlazaRequireAuth *bool   `json:"model_plaza_require_auth"`
@@ -1937,6 +1940,12 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 			}
 			return previousSettings.AvailableChannelsEnabled
 		}(),
+		SubscriptionEnabled: func() bool {
+			if req.SubscriptionEnabled != nil {
+				return *req.SubscriptionEnabled
+			}
+			return previousSettings.SubscriptionEnabled
+		}(),
 		ModelPlazaEnabled: func() bool {
 			if req.ModelPlazaEnabled != nil {
 				return *req.ModelPlazaEnabled
@@ -2380,6 +2389,7 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 		GrokDefaultBaseURLMode:         updatedSettings.GrokDefaultBaseURLMode,
 
 		AvailableChannelsEnabled: updatedSettings.AvailableChannelsEnabled,
+		SubscriptionEnabled:      updatedSettings.SubscriptionEnabled,
 
 		ModelPlazaEnabled:       updatedSettings.ModelPlazaEnabled,
 		ModelPlazaRequireAuth:   updatedSettings.ModelPlazaRequireAuth,

backend/internal/handler/dto/settings.go

@@ -317,6 +317,10 @@ type SystemSettings struct {
 	// Available Channels feature switch (user-facing aggregate view)
 	AvailableChannelsEnabled bool `json:"available_channels_enabled"`
 
+	// Subscription feature switch: gates the whole user-facing subscription surface
+	// (sidebar entries, purchase-page subscription tab, header badge, /subscriptions route).
+	SubscriptionEnabled bool `json:"subscription_enabled"`
+
 	// Model Plaza feature (public group/model pricing showcase)
 	ModelPlazaEnabled       bool   `json:"model_plaza_enabled"`
 	ModelPlazaRequireAuth   bool   `json:"model_plaza_require_auth"`
@@ -403,7 +407,11 @@ type PublicSettings struct {
 	GoogleOAuthEnabled                  bool                     `json:"google_oauth_enabled"`
 	BackendModeEnabled                  bool                     `json:"backend_mode_enabled"`
 	PaymentEnabled                      bool                     `json:"payment_enabled"`
-	Version                             string                   `json:"version"`
+	// PaymentBalanceDisabled mirrors the payment-config BALANCE_PAYMENT_DISABLED switch so the
+	// user shell can derive the site billing mode (recharge & subscription / recharge only /
+	// subscription only) before any authenticated checkout call.
+	PaymentBalanceDisabled bool   `json:"payment_balance_disabled"`
+	Version                string `json:"version"`
 	// 服务器全局时区（IANA 名称与当前 UTC 偏移，如 "Asia/Shanghai" / "+08:00"）。
 	// 高峰时段等按服务器本地时间判定的窗口，前端展示时据此标注，避免用户按浏览器本地时间误读。
 	ServerTimezone              string  `json:"server_timezone"`
@@ -422,6 +430,8 @@ type PublicSettings struct {
 
 	AvailableChannelsEnabled bool `json:"available_channels_enabled"`
 
+	SubscriptionEnabled bool `json:"subscription_enabled"`
+
 	ModelPlazaEnabled       bool `json:"model_plaza_enabled"`
 	ModelPlazaRequireAuth   bool `json:"model_plaza_require_auth"`
 	PluginManagementEnabled bool `json:"plugin_management_enabled"`

backend/internal/handler/setting_handler.go

@@ -95,6 +95,7 @@ func (h *SettingHandler) GetPublicSettings(c *gin.Context) {
 		GoogleOAuthEnabled:                  settings.GoogleOAuthEnabled,
 		BackendModeEnabled:                  settings.BackendModeEnabled,
 		PaymentEnabled:                      settings.PaymentEnabled,
+		PaymentBalanceDisabled:              settings.PaymentBalanceDisabled,
 		Version:                             h.version,
 		ServerTimezone:                      timezone.Name(),
 		ServerUTCOffset:                     timezone.UTCOffset(),
@@ -111,6 +112,7 @@ func (h *SettingHandler) GetPublicSettings(c *gin.Context) {
 		ChannelMonitorHideUserRanking:        settings.ChannelMonitorHideUserRanking,
 
 		AvailableChannelsEnabled: settings.AvailableChannelsEnabled,
+		SubscriptionEnabled:      settings.SubscriptionEnabled,
 
 		ModelPlazaEnabled:       settings.ModelPlazaEnabled,
 		ModelPlazaRequireAuth:   settings.ModelPlazaRequireAuth,

backend/internal/server/api_contract_test.go

@@ -995,6 +995,7 @@ func TestAPIContracts(t *testing.T) {
 					"channel_monitor_hide_user_ranking": false,
 					"channel_monitor_default_interval_seconds": 60,
 					"available_channels_enabled": false,
+					"subscription_enabled": true,
 					"model_plaza_enabled": false,
 					"model_plaza_require_auth": false,
 					"model_plaza_description": "",
@@ -1309,6 +1310,7 @@ func TestAPIContracts(t *testing.T) {
 					"channel_monitor_hide_user_ranking": false,
 					"channel_monitor_default_interval_seconds": 60,
 					"available_channels_enabled": false,
+					"subscription_enabled": true,
 					"model_plaza_enabled": false,
 					"model_plaza_require_auth": false,
 					"model_plaza_description": "",

backend/internal/service/domain_constants.go

@@ -513,6 +513,15 @@ const (
 	// sidebar entry is hidden. Defaults to false (opt-in feature).
 	SettingKeyAvailableChannelsEnabled = "available_channels_enabled"
 
+	// SettingKeySubscriptionEnabled is a DB-backed soft switch for the user-facing
+	// subscription surface: sidebar entries, purchase-page subscription tab, header
+	// progress badge, usage billing-type filter and the /subscriptions route. When
+	// false users can no longer buy or browse subscriptions from the UI; the
+	// subscriptions API, existing subscription billing and admin subscription
+	// management are unaffected. Together with BALANCE_PAYMENT_DISABLED it forms the
+	// admin "site billing mode" selector. Defaults to true (opt-out feature).
+	SettingKeySubscriptionEnabled = "subscription_enabled"
+
 	// SettingKeyModelPlazaEnabled is a DB-backed soft switch for the Model Plaza page
 	// (public group/model pricing showcase). When false: the plaza endpoint returns 404
 	// and the header entry is hidden. Defaults to false (opt-in feature).

backend/internal/service/setting_parse.go

@@ -202,6 +202,9 @@ func (s *SettingService) InitializeDefaultSettings(ctx context.Context) error {
 		// Available channels feature (default disabled; opt-in)
 		SettingKeyAvailableChannelsEnabled: "false",
 
+		// Subscription feature (default enabled; opt-out)
+		SettingKeySubscriptionEnabled: "true",
+
 		// Model plaza feature (default disabled; opt-in, public unless require_auth)
 		SettingKeyModelPlazaEnabled:       "false",
 		SettingKeyModelPlazaRequireAuth:   "false",
@@ -820,6 +823,9 @@ func (s *SettingService) parseSettings(settings map[string]string) *SystemSettin
 	// Available channels feature (default: disabled; strict true)
 	result.AvailableChannelsEnabled = settings[SettingKeyAvailableChannelsEnabled] == "true"
 
+	// Subscription feature (default: enabled; only an explicit false disables)
+	result.SubscriptionEnabled = !isFalseSettingValue(settings[SettingKeySubscriptionEnabled])
+
 	// Model plaza feature (default: disabled; strict true)
 	result.ModelPlazaEnabled = settings[SettingKeyModelPlazaEnabled] == "true"
 	result.ModelPlazaRequireAuth = settings[SettingKeyModelPlazaRequireAuth] == "true"

backend/internal/service/setting_public.go

@@ -215,6 +215,7 @@ func (s *SettingService) GetPublicSettings(ctx context.Context) (*PublicSettings
 		SettingKeyWeChatConnectFrontendRedirectURL,
 		SettingKeyBackendModeEnabled,
 		SettingPaymentEnabled,
+		SettingBalancePayDisabled,
 		SettingKeyOIDCConnectEnabled,
 		SettingKeyOIDCConnectProviderName,
 		SettingKeyGitHubOAuthEnabled,
@@ -234,6 +235,7 @@ func (s *SettingService) GetPublicSettings(ctx context.Context) (*PublicSettings
 		SettingKeyChannelMonitorShowQuota,
 		SettingKeyChannelMonitorHideUserRanking,
 		SettingKeyAvailableChannelsEnabled,
+		SettingKeySubscriptionEnabled,
 		SettingKeyModelPlazaEnabled,
 		SettingKeyModelPlazaRequireAuth,
 		SettingKeyPluginManagementEnabled,
@@ -345,6 +347,7 @@ func (s *SettingService) GetPublicSettings(ctx context.Context) (*PublicSettings
 		WeChatOAuthMobileEnabled:            weChatMobileEnabled,
 		BackendModeEnabled:                  settings[SettingKeyBackendModeEnabled] == "true",
 		PaymentEnabled:                      settings[SettingPaymentEnabled] == "true",
+		PaymentBalanceDisabled:              settings[SettingBalancePayDisabled] == "true",
 		OIDCOAuthEnabled:                    oidcEnabled,
 		OIDCOAuthProviderName:               oidcProviderName,
 		GitHubOAuthEnabled:                  gitHubEnabled,
@@ -363,6 +366,8 @@ func (s *SettingService) GetPublicSettings(ctx context.Context) (*PublicSettings
 
 		AvailableChannelsEnabled: settings[SettingKeyAvailableChannelsEnabled] == "true",
 
+		SubscriptionEnabled: !isFalseSettingValue(settings[SettingKeySubscriptionEnabled]),
+
 		ModelPlazaEnabled:       settings[SettingKeyModelPlazaEnabled] == "true",
 		ModelPlazaRequireAuth:   settings[SettingKeyModelPlazaRequireAuth] == "true",
 		PluginManagementEnabled: settings[SettingKeyPluginManagementEnabled] == "true",
@@ -605,6 +610,7 @@ type PublicSettingsInjectionPayload struct {
 	GoogleOAuthEnabled                  bool                     `json:"google_oauth_enabled"`
 	BackendModeEnabled                  bool                     `json:"backend_mode_enabled"`
 	PaymentEnabled                      bool                     `json:"payment_enabled"`
+	PaymentBalanceDisabled              bool                     `json:"payment_balance_disabled"`
 	Version                             string                   `json:"version"`
 	// 服务器全局时区（IANA 名称与当前 UTC 偏移），高峰时段等服务端本地时间窗口的展示标注用
 	ServerTimezone              string  `json:"server_timezone"`
@@ -630,6 +636,7 @@ type PublicSettingsInjectionPayload struct {
 	ChannelMonitorHideUserRanking bool `json:"channel_monitor_hide_user_ranking"`
 	ChannelMonitorShowQuota       bool `json:"channel_monitor_show_quota"`
 	AvailableChannelsEnabled      bool `json:"available_channels_enabled"`
+	SubscriptionEnabled           bool `json:"subscription_enabled"`
 	ModelPlazaEnabled             bool `json:"model_plaza_enabled"`
 	ModelPlazaRequireAuth         bool `json:"model_plaza_require_auth"`
 	PluginManagementEnabled       bool `json:"plugin_management_enabled"`
@@ -697,6 +704,7 @@ func (s *SettingService) GetPublicSettingsForInjection(ctx context.Context) (any
 		GoogleOAuthEnabled:                  settings.GoogleOAuthEnabled,
 		BackendModeEnabled:                  settings.BackendModeEnabled,
 		PaymentEnabled:                      settings.PaymentEnabled,
+		PaymentBalanceDisabled:              settings.PaymentBalanceDisabled,
 		Version:                             s.version,
 		ServerTimezone:                      timezone.Name(),
 		ServerUTCOffset:                     timezone.UTCOffset(),
@@ -712,6 +720,7 @@ func (s *SettingService) GetPublicSettingsForInjection(ctx context.Context) (any
 		ChannelMonitorShowQuota:              settings.ChannelMonitorShowQuota,
 		ChannelMonitorHideUserRanking:        settings.ChannelMonitorHideUserRanking,
 		AvailableChannelsEnabled:             settings.AvailableChannelsEnabled,
+		SubscriptionEnabled:                  settings.SubscriptionEnabled,
 		ModelPlazaEnabled:                    settings.ModelPlazaEnabled,
 		ModelPlazaRequireAuth:                settings.ModelPlazaRequireAuth,
 		PluginManagementEnabled:              settings.PluginManagementEnabled,

backend/internal/service/setting_service_public_test.go

@@ -240,3 +240,72 @@ func TestSettingService_GetPublicSettings_FallsBackToConfigForWeChatOAuthCapabil
 	require.False(t, settings.WeChatOAuthMPEnabled)
 	require.False(t, settings.WeChatOAuthMobileEnabled)
 }
+
+// subscription_enabled gates the user-facing "My Subscriptions" sidebar entry and
+// is opt-out: only an explicit "false" hides it.
+func TestSettingService_GetPublicSettings_SubscriptionEnabledOnlyExplicitFalseDisables(t *testing.T) {
+	cases := []struct {
+		name   string
+		values map[string]string
+		want   bool
+	}{
+		{name: "missing key defaults to enabled", values: map[string]string{}, want: true},
+		{name: "empty value stays enabled", values: map[string]string{SettingKeySubscriptionEnabled: ""}, want: true},
+		{name: "explicit true", values: map[string]string{SettingKeySubscriptionEnabled: "true"}, want: true},
+		{name: "explicit false disables", values: map[string]string{SettingKeySubscriptionEnabled: "false"}, want: false},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			svc := NewSettingService(&settingPublicRepoStub{values: tc.values}, &config.Config{})
+
+			settings, err := svc.GetPublicSettings(context.Background())
+			require.NoError(t, err)
+			require.Equal(t, tc.want, settings.SubscriptionEnabled)
+		})
+	}
+}
+
+// The SSR injection payload must mirror the switch so the opt-out flag does not
+// flicker off on first render before the async public-settings fetch resolves.
+func TestSettingService_GetPublicSettingsForInjection_MirrorsSubscriptionEnabled(t *testing.T) {
+	for _, value := range []string{"false", "true"} {
+		repo := &settingPublicRepoStub{values: map[string]string{SettingKeySubscriptionEnabled: value}}
+		svc := NewSettingService(repo, &config.Config{})
+
+		raw, err := svc.GetPublicSettingsForInjection(context.Background())
+		require.NoError(t, err)
+		payload, ok := raw.(*PublicSettingsInjectionPayload)
+		require.True(t, ok)
+		require.Equal(t, value == "true", payload.SubscriptionEnabled, "value=%q", value)
+	}
+}
+
+// payment_balance_disabled is exposed publicly so the user shell can derive the site
+// billing mode (recharge & subscription / recharge only / subscription only) before any
+// authenticated checkout call. Strict true, mirroring the payment-config parser.
+func TestSettingService_GetPublicSettings_PaymentBalanceDisabledStrictTrue(t *testing.T) {
+	cases := []struct {
+		name  string
+		value map[string]string
+		want  bool
+	}{
+		{name: "missing key stays enabled", value: map[string]string{}, want: false},
+		{name: "explicit false", value: map[string]string{SettingBalancePayDisabled: "false"}, want: false},
+		{name: "explicit true disables balance recharge", value: map[string]string{SettingBalancePayDisabled: "true"}, want: true},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			svc := NewSettingService(&settingPublicRepoStub{values: tc.value}, &config.Config{})
+
+			settings, err := svc.GetPublicSettings(context.Background())
+			require.NoError(t, err)
+			require.Equal(t, tc.want, settings.PaymentBalanceDisabled)
+
+			raw, err := svc.GetPublicSettingsForInjection(context.Background())
+			require.NoError(t, err)
+			payload, ok := raw.(*PublicSettingsInjectionPayload)
+			require.True(t, ok)
+			require.Equal(t, tc.want, payload.PaymentBalanceDisabled)
+		})
+	}
+}

backend/internal/service/setting_update.go

@@ -432,6 +432,9 @@ func (s *SettingService) buildSystemSettingsUpdates(ctx context.Context, setting
 	// Available channels feature switch
 	updates[SettingKeyAvailableChannelsEnabled] = strconv.FormatBool(settings.AvailableChannelsEnabled)
 
+	// Subscription feature switch
+	updates[SettingKeySubscriptionEnabled] = strconv.FormatBool(settings.SubscriptionEnabled)
+
 	// Model plaza feature switches + description
 	updates[SettingKeyModelPlazaEnabled] = strconv.FormatBool(settings.ModelPlazaEnabled)
 	updates[SettingKeyModelPlazaRequireAuth] = strconv.FormatBool(settings.ModelPlazaRequireAuth)

backend/internal/service/settings_view.go

@@ -212,6 +212,12 @@ type SystemSettings struct {
 	// Available Channels feature (user-facing aggregate view)
 	AvailableChannelsEnabled bool `json:"available_channels_enabled"`
 
+	// Subscription feature switch: gates the whole user-facing subscription surface
+	// (sidebar entries, purchase-page subscription tab, header progress badge,
+	// usage billing-type filter, /subscriptions route). Pairs with PaymentBalanceDisabled
+	// to form the admin-facing "site billing mode" selector.
+	SubscriptionEnabled bool `json:"subscription_enabled"`
+
 	// Model Plaza feature (public group/model pricing showcase)
 	ModelPlazaEnabled       bool   `json:"model_plaza_enabled"`
 	ModelPlazaRequireAuth   bool   `json:"model_plaza_require_auth"`
@@ -366,6 +372,7 @@ type PublicSettings struct {
 	WeChatOAuthMobileEnabled bool
 	BackendModeEnabled       bool
 	PaymentEnabled           bool
+	PaymentBalanceDisabled   bool
 	OIDCOAuthEnabled         bool
 	OIDCOAuthProviderName    string
 	GitHubOAuthEnabled       bool
@@ -393,6 +400,9 @@ type PublicSettings struct {
 	// Available Channels feature (user-facing aggregate view)
 	AvailableChannelsEnabled bool `json:"available_channels_enabled"`
 
+	// Subscription feature switch (see SystemSettings.SubscriptionEnabled)
+	SubscriptionEnabled bool `json:"subscription_enabled"`
+
 	// Model Plaza feature (public group/model pricing showcase)
 	ModelPlazaEnabled       bool `json:"model_plaza_enabled"`
 	ModelPlazaRequireAuth   bool `json:"model_plaza_require_auth"`

frontend/src/App.vue

@@ -1,6 +1,6 @@
 <script setup lang="ts">
 import { RouterView, useRouter, useRoute } from 'vue-router'
-import { onMounted, onBeforeUnmount, watch } from 'vue'
+import { computed, onMounted, onBeforeUnmount, watch } from 'vue'
 import Toast from '@/components/common/Toast.vue'
 import NavigationProgress from '@/components/common/NavigationProgress.vue'
 import AdminComplianceDialog from '@/components/admin/AdminComplianceDialog.vue'
@@ -9,6 +9,8 @@ import AnnouncementPopup from '@/components/common/AnnouncementPopup.vue'
 import { useAppStore, useAuthStore, useSubscriptionStore, useAnnouncementStore, useAdminComplianceStore, useAdminSettingsStore } from '@/stores'
 import { getSetupStatus } from '@/api/setup'
 import { updateFavicon } from '@/utils/branding'
+import { FeatureFlags, isFeatureFlagEnabled } from '@/utils/featureFlags'
+import { resolveSiteBillingMode } from '@/utils/siteBillingMode'
 
 const router = useRouter()
 const route = useRoute()
@@ -24,7 +26,9 @@ function updateDocumentTitle() {
     ...(appStore.cachedPublicSettings?.custom_menu_items ?? []),
     ...(authStore.isAdmin ? adminSettingsStore.customMenuItems : []),
   ]
-  document.title = resolveRouteDocumentTitle(route, appStore.siteName, customMenuItems)
+  document.title = resolveRouteDocumentTitle(route, appStore.siteName, customMenuItems, {
+    billingMode: resolveSiteBillingMode(appStore.cachedPublicSettings),
+  })
 }
 
 // Watch for site settings changes and update favicon/title
@@ -45,6 +49,8 @@ watch(
     () => route.meta.titleKey,
     () => appStore.siteName,
     () => appStore.cachedPublicSettings?.custom_menu_items,
+    () => appStore.cachedPublicSettings?.subscription_enabled,
+    () => appStore.cachedPublicSettings?.payment_balance_disabled,
     () => authStore.isAdmin,
     () => adminSettingsStore.customMenuItems,
   ],
@@ -64,6 +70,25 @@ function onAdminComplianceRequired(event: Event) {
   adminComplianceStore.requireAcknowledgement(detail)
 }
 
+// 订阅功能开关（opt-out）。关闭后不再预加载/轮询订阅接口；开关在登录后才到达时补启动，反向则清空。
+const subscriptionFeatureEnabled = computed(() => isFeatureFlagEnabled(FeatureFlags.subscription))
+
+function startSubscriptionSync() {
+  subscriptionStore.fetchActiveSubscriptions().catch((error) => {
+    console.error('Failed to preload subscriptions:', error)
+  })
+  subscriptionStore.startPolling()
+}
+
+watch(subscriptionFeatureEnabled, (enabled) => {
+  if (!authStore.isAuthenticated) return
+  if (enabled) {
+    startSubscriptionSync()
+  } else {
+    subscriptionStore.clear()
+  }
+})
+
 watch(
   () => authStore.isAuthenticated,
   (isAuthenticated, oldValue) => {
@@ -74,11 +99,11 @@ watch(
         })
       }
 
-      // User logged in: preload subscriptions and start polling
-      subscriptionStore.fetchActiveSubscriptions().catch((error) => {
-        console.error('Failed to preload subscriptions:', error)
-      })
-      subscriptionStore.startPolling()
+      // User logged in: preload subscriptions and start polling (skipped when the
+      // subscription feature is switched off; see the flag watcher below)
+      if (subscriptionFeatureEnabled.value) {
+        startSubscriptionSync()
+      }
 
       // Announcements: new login vs page refresh restore
       if (oldValue === false) {

frontend/src/api/admin/settings.ts

@@ -727,6 +727,9 @@ export interface SystemSettings {
   // Available Channels feature switch
   available_channels_enabled: boolean;
 
+  // Subscription feature switch (user sidebar "My Subscriptions" entry)
+  subscription_enabled: boolean;
+
   // Model Plaza feature switches + description
   model_plaza_enabled: boolean;
   model_plaza_require_auth: boolean;
@@ -1029,6 +1032,9 @@ export interface UpdateSettingsRequest {
   // Available Channels feature switch
   available_channels_enabled?: boolean;
 
+  // Subscription feature switch
+  subscription_enabled?: boolean;
+
   // Model Plaza feature switches + description
   model_plaza_enabled?: boolean;
   model_plaza_require_auth?: boolean;

frontend/src/components/common/SubscriptionProgressMini.vue

@@ -1,5 +1,5 @@
 <template>
-  <div v-if="hasActiveSubscriptions" class="relative" ref="containerRef">
+  <div v-if="subscriptionFeatureEnabled && hasActiveSubscriptions" class="relative" ref="containerRef">
     <!-- Mini Progress Display -->
     <button
       @click="toggleTooltip"
@@ -182,6 +182,7 @@ import { ref, computed, onMounted, onBeforeUnmount } from 'vue'
 import { useI18n } from 'vue-i18n'
 import Icon from '@/components/icons/Icon.vue'
 import { useSubscriptionStore } from '@/stores'
+import { FeatureFlags, isFeatureFlagEnabled } from '@/utils/featureFlags'
 import type { UserSubscription } from '@/types'
 
 const { t } = useI18n()
@@ -194,6 +195,8 @@ const tooltipOpen = ref(false)
 // Use store data instead of local state
 const activeSubscriptions = computed(() => subscriptionStore.activeSubscriptions)
 const hasActiveSubscriptions = computed(() => subscriptionStore.hasActiveSubscriptions)
+// 订阅功能关闭后，即使用户仍持有后台分配的订阅，顶栏也不再露出订阅进度与「查看全部订阅」入口。
+const subscriptionFeatureEnabled = computed(() => isFeatureFlagEnabled(FeatureFlags.subscription))
 
 const displaySubscriptions = computed(() => {
   // Sort by most usage (highest percentage first)
@@ -296,6 +299,7 @@ onMounted(() => {
   document.addEventListener('click', handleClickOutside)
   // Trigger initial fetch if not already loaded
   // The actual data loading is handled by App.vue globally
+  if (!subscriptionFeatureEnabled.value) return
   subscriptionStore.fetchActiveSubscriptions().catch((error) => {
     console.error('Failed to load subscriptions in SubscriptionProgressMini:', error)
   })

frontend/src/components/layout/AppHeader.vue

@@ -51,8 +51,8 @@
         <!-- Language Switcher -->
         <LocaleSwitcher />
 
-        <!-- Subscription Progress (for users with active subscriptions) -->
-        <SubscriptionProgressMini v-if="user" />
+        <!-- Subscription Progress (for users with active subscriptions; not mounted at all when the feature is off) -->
+        <SubscriptionProgressMini v-if="user && subscriptionFeatureEnabled" />
 
         <!-- Balance Display -->
         <div
@@ -261,6 +261,8 @@ import AnnouncementBell from '@/components/common/AnnouncementBell.vue'
 import Icon from '@/components/icons/Icon.vue'
 import { sanitizeUrl } from '@/utils/url'
 import { FeatureFlags, isFeatureFlagEnabled } from '@/utils/featureFlags'
+import { resolveRouteMetaKeys } from '@/router/title'
+import { resolveSiteBillingMode } from '@/utils/siteBillingMode'
 
 const router = useRouter()
 const route = useRoute()
@@ -309,6 +311,14 @@ const displayName = computed(() => {
   return user.value.username || user.value.email?.split('@')[0] || ''
 })
 
+// 订阅功能关闭时不挂载顶栏订阅徽章（组件 onMounted 会拉取订阅接口）。
+const subscriptionFeatureEnabled = computed(() => isFeatureFlagEnabled(FeatureFlags.subscription))
+
+// /purchase 的标题/描述随站点计费模式切换，与 document.title 共用同一解析。
+const routeMetaKeys = computed(() => resolveRouteMetaKeys(route, {
+  billingMode: resolveSiteBillingMode(appStore.cachedPublicSettings),
+}))
+
 const pageTitle = computed(() => {
   // For custom pages, use the menu item's label instead of generic "自定义页面"
   if (route.name === 'CustomPage') {
@@ -318,7 +328,7 @@ const pageTitle = computed(() => {
       ?? (authStore.isAdmin ? adminSettingsStore.customMenuItems.find((item) => item.id === id) : undefined)
     if (menuItem?.label) return menuItem.label
   }
-  const titleKey = route.meta.titleKey as string
+  const titleKey = routeMetaKeys.value.titleKey
   if (titleKey) {
     return t(titleKey)
   }
@@ -326,7 +336,7 @@ const pageTitle = computed(() => {
 })
 
 const pageDescription = computed(() => {
-  const descKey = route.meta.descriptionKey as string
+  const descKey = routeMetaKeys.value.descriptionKey
   if (descKey) {
     return t(descKey)
   }

frontend/src/components/layout/AppSidebar.vue

@@ -197,6 +197,7 @@ import Icon from '@/components/icons/Icon.vue'
 import { sanitizeSvg } from '@/utils/sanitize'
 import { sanitizeUrl } from '@/utils/url'
 import { FeatureFlags, makeSidebarFlag } from '@/utils/featureFlags'
+import { resolveSiteBillingMode } from '@/utils/siteBillingMode'
 import { useBatchImageAccess } from '@/composables/useBatchImageAccess'
 
 interface NavItem {
@@ -691,6 +692,19 @@ const ChevronDownIcon = {
 const flagChannelMonitor = makeSidebarFlag(FeatureFlags.channelMonitor)
 const flagPayment = makeSidebarFlag(FeatureFlags.payment)
 const flagAvailableChannels = makeSidebarFlag(FeatureFlags.availableChannels)
+const flagSubscription = makeSidebarFlag(FeatureFlags.subscription)
+
+// 购买入口文案随站点计费模式切换：仅充值 → 「充值」，仅订阅 → 「订阅」，否则「充值/订阅」。
+const purchaseNavLabel = computed(() => {
+  switch (resolveSiteBillingMode(appStore.cachedPublicSettings)) {
+    case 'recharge_only':
+      return t('nav.recharge')
+    case 'subscription_only':
+      return t('nav.subscribe')
+    default:
+      return t('nav.buySubscription')
+  }
+})
 const flagAffiliate = makeSidebarFlag(FeatureFlags.affiliate)
 const flagRiskControl = makeSidebarFlag(FeatureFlags.riskControl)
 const flagPluginManagement = makeSidebarFlag(FeatureFlags.pluginManagement)
@@ -714,8 +728,8 @@ function buildSelfNavItems(withDashboard: boolean): NavItem[] {
     { path: '/usage', label: t('nav.usage'), icon: ChartIcon, hideInSimpleMode: true },
     { path: '/available-channels', label: t('nav.availableChannels'), icon: ChannelIcon, hideInSimpleMode: true, featureFlag: flagAvailableChannels },
     { path: '/monitor', label: t('nav.channelStatus'), icon: SignalIcon, featureFlag: flagChannelMonitor },
-    { path: '/subscriptions', label: t('nav.mySubscriptions'), icon: CreditCardIcon, hideInSimpleMode: true },
-    { path: '/purchase', label: t('nav.buySubscription'), icon: RechargeSubscriptionIcon, hideInSimpleMode: true, featureFlag: flagPayment },
+    { path: '/subscriptions', label: t('nav.mySubscriptions'), icon: CreditCardIcon, hideInSimpleMode: true, featureFlag: flagSubscription },
+    { path: '/purchase', label: purchaseNavLabel.value, icon: RechargeSubscriptionIcon, hideInSimpleMode: true, featureFlag: flagPayment },
     { path: '/orders', label: t('nav.myOrders'), icon: OrderListIcon, hideInSimpleMode: true, featureFlag: flagPayment },
     { path: '/redeem', label: t('nav.redeem'), icon: GiftIcon, hideInSimpleMode: true },
     { path: '/affiliate', label: t('nav.affiliate'), icon: UsersIcon, hideInSimpleMode: true, featureFlag: flagAffiliate },
@@ -776,7 +790,8 @@ const adminNavItems = computed((): NavItem[] => {
         { path: '/admin/channels/monitor', label: t('nav.channelMonitor'), icon: SignalIcon, featureFlag: flagChannelMonitor },
       ],
     },
-    { path: '/admin/subscriptions', label: t('nav.subscriptions'), icon: CreditCardIcon, hideInSimpleMode: true },
+    // 「仅充值」站点连管理端的「订阅管理」入口也一并收起（路由本身不拦截）。
+    { path: '/admin/subscriptions', label: t('nav.subscriptions'), icon: CreditCardIcon, hideInSimpleMode: true, featureFlag: flagSubscription },
     { path: '/admin/accounts', label: t('nav.accounts'), icon: GlobeIcon },
     { path: '/admin/plugins', label: t('nav.plugins'), icon: PluginIcon, featureFlag: flagPluginManagement },
     { path: '/admin/announcements', label: t('nav.announcements'), icon: BellIcon },

frontend/src/components/layout/__tests__/AppSidebar.spec.ts

@@ -62,3 +62,21 @@ describe('AppSidebar header styles', () => {
     expect(sidebarBrandBlockMatch?.[0]).not.toContain('overflow: hidden;')
   })
 })
+
+describe('AppSidebar subscription feature flag', () => {
+  it('gates the My Subscriptions entry behind the subscription public-settings flag', () => {
+    expect(componentSource).toContain('const flagSubscription = makeSidebarFlag(FeatureFlags.subscription)')
+    expect(componentSource).toMatch(/path: '\/subscriptions'[^\n]*featureFlag: flagSubscription/)
+  })
+
+  it('also hides the admin Subscription Management entry on recharge-only sites', () => {
+    expect(componentSource).toMatch(/path: '\/admin\/subscriptions'[^\n]*featureFlag: flagSubscription/)
+  })
+
+  it('derives the purchase entry label from the site billing mode', () => {
+    expect(componentSource).toContain("import { resolveSiteBillingMode } from '@/utils/siteBillingMode'")
+    expect(componentSource).toMatch(/case 'recharge_only':\s*return t\('nav\.recharge'\)/)
+    expect(componentSource).toMatch(/case 'subscription_only':\s*return t\('nav\.subscribe'\)/)
+    expect(componentSource).toMatch(/path: '\/purchase'[^\n]*label: purchaseNavLabel\.value/)
+  })
+})

frontend/src/i18n/locales/en/admin/settings.ts

@@ -45,6 +45,21 @@ export default {
           enabled: 'Enable Available Channels',
           enabledHint: 'When off, the sidebar entry is hidden and the endpoint returns an empty list.',
         },
+        siteBillingMode: {
+          title: 'Site Billing Mode',
+          description: 'Controls which purchase options users see. Defaults to "Recharge & Subscription".',
+          label: 'Purchase options',
+          options: {
+            rechargeAndSubscription: 'Recharge & Subscription',
+            rechargeOnly: 'Recharge only',
+            subscriptionOnly: 'Subscription only',
+          },
+          hints: {
+            rechargeAndSubscription: 'Users can both top up their balance and buy subscription plans.',
+            rechargeOnly: 'Hides "My Subscriptions", the purchase-page subscription tab, the header subscription badge and the usage billing-type filter; direct visits to "My Subscriptions" return to the dashboard. The admin sidebar also hides the "Subscription Management" entry (the page stays reachable by URL). Existing subscription billing and redeem-code subscriptions are unaffected.',
+            subscriptionOnly: 'The purchase page only offers subscription plans and the sidebar entry reads "Subscription"; balance top-up orders are rejected. Redeem codes, affiliate payouts and other balance credits are unaffected.',
+          },
+        },
         modelPlaza: {
           title: 'Model Plaza',
           description: 'A public page showcasing available models and pricing by group. Disabled by default.',

frontend/src/i18n/locales/en/common.ts

@@ -197,6 +197,8 @@ export default {
     github: 'GitHub',
     mySubscriptions: 'My Subscriptions',
     buySubscription: 'Recharge / Subscription',
+    recharge: 'Recharge',
+    subscribe: 'Subscription',
     docs: 'Docs',
     myOrders: 'My Orders',
     orderManagement: 'Orders',

frontend/src/i18n/locales/en/landing.ts

@@ -163,6 +163,7 @@ export default {
     usedQuota: 'Used Quota',
     resetNow: 'Resetting soon',
     subscriptionType: 'Subscription Type',
+    billingType: 'Billing Type',
     subscriptionExpires: 'Subscription Expires',
     // Usage stat cells
     todayRequests: 'Today Requests',

frontend/src/i18n/locales/en/misc.ts

@@ -63,6 +63,8 @@ export default {
   purchase: {
     title: 'Recharge / Subscription',
     description: 'Recharge balance or purchase subscription via the embedded page',
+    rechargeDescription: 'Recharge balance via the embedded page',
+    subscriptionDescription: 'Purchase subscription via the embedded page',
     openInNewTab: 'Open in new tab',
     notEnabledTitle: 'Feature not enabled',
     notEnabledDesc: 'The administrator has not enabled the recharge/subscription entry. Please contact admin.',
@@ -385,6 +387,7 @@ export default {
     tabSubscribe: 'Subscribe',
     noPlans: 'No subscription plans available',
     notAvailable: 'Top-up is currently unavailable',
+    billingUnavailable: 'Neither top-up nor subscriptions are currently available. Please contact the administrator.',
     confirmSubscription: 'Confirm Subscription',
     confirmCancel: 'Are you sure you want to cancel this order?',
     amountTooLow: 'Minimum amount is {min}',

frontend/src/i18n/locales/zh/admin/settings.ts

@@ -45,6 +45,21 @@ export default {
           enabled: '启用可用渠道',
           enabledHint: '关闭后用户端侧边栏入口隐藏，接口返回空数组。',
         },
+        siteBillingMode: {
+          title: '站点类型',
+          description: '决定用户端提供哪些购买方式。默认「充值 & 订阅」。',
+          label: '购买方式',
+          options: {
+            rechargeAndSubscription: '充值 & 订阅',
+            rechargeOnly: '仅充值',
+            subscriptionOnly: '仅订阅',
+          },
+          hints: {
+            rechargeAndSubscription: '用户端同时提供余额充值与订阅套餐。',
+            rechargeOnly: '用户端隐藏「我的订阅」、购买页订阅套餐、顶栏订阅进度与用量页「计费类型」筛选，直接访问「我的订阅」会跳回仪表盘；管理端侧边栏同时隐藏「订阅管理」入口（页面仍可通过地址访问）。已有订阅的计费与兑换码发放的订阅不受影响。',
+            subscriptionOnly: '用户端购买页只保留订阅套餐，侧边栏入口显示为「订阅」，余额充值下单会被拒绝；兑换码、返利等余额入账不受影响。',
+          },
+        },
         modelPlaza: {
           title: '模型广场',
           description: '以分组为单位向访客展示可用模型与价格的公开页面。默认关闭。',

frontend/src/i18n/locales/zh/common.ts

@@ -197,6 +197,8 @@ export default {
     github: 'GitHub',
     mySubscriptions: '我的订阅',
     buySubscription: '充值/订阅',
+    recharge: '充值',
+    subscribe: '订阅',
     docs: '文档',
     myOrders: '我的订单',
     orderManagement: '订单管理',

frontend/src/i18n/locales/zh/landing.ts

@@ -163,6 +163,7 @@ export default {
     usedQuota: '已用额度',
     resetNow: '即将重置',
     subscriptionType: '订阅类型',
+    billingType: '计费方式',
     subscriptionExpires: '订阅到期',
     // Usage stat cells
     todayRequests: '今日请求',

frontend/src/i18n/locales/zh/misc.ts

@@ -62,6 +62,8 @@ export default {
   purchase: {
     title: '充值/订阅',
     description: '通过内嵌页面完成充值/订阅',
+    rechargeDescription: '通过内嵌页面完成充值',
+    subscriptionDescription: '通过内嵌页面完成订阅',
     openInNewTab: '新窗口打开',
     notEnabledTitle: '该功能未开启',
     notEnabledDesc: '管理员暂未开启充值/订阅入口，请联系管理员。',
@@ -409,6 +411,7 @@ export default {
     tabSubscribe: '订阅',
     noPlans: '暂无可用订阅套餐',
     notAvailable: '充值功能暂未开放',
+    billingUnavailable: '充值与订阅均暂未开放，请联系管理员。',
     confirmSubscription: '确认订阅',
     confirmCancel: '确定要取消此订单吗？',
     amountTooLow: '最低金额为 {min}',

frontend/src/router/__tests__/feature-access.spec.ts

@@ -25,6 +25,7 @@ const appStore = vi.hoisted(() => ({
   cachedPublicSettings: null as null | {
     payment_enabled?: boolean
     risk_control_enabled?: boolean
+    subscription_enabled?: boolean
     custom_menu_items?: []
   },
   fetchPublicSettings: vi.fn(),
@@ -142,6 +143,7 @@ describe('feature route guard', () => {
   it.each([
     ['payment', { requiresPayment: true }, '/purchase'],
     ['risk control', { requiresRiskControl: true }, '/admin/risk-control'],
+    ['subscription', { requiresSubscription: true }, '/subscriptions'],
   ])('does not treat a failed %s settings load as explicitly disabled', async (_name, meta, path) => {
     authStore.isAdmin = meta.requiresRiskControl === true
     appStore.fetchPublicSettings.mockResolvedValue(null)
@@ -162,6 +164,7 @@ describe('feature route guard', () => {
       { risk_control_enabled: false },
       '/admin/settings',
     ],
+    ['subscription', { requiresSubscription: true }, { subscription_enabled: false }, '/dashboard'],
   ])('redirects when loaded settings explicitly disable %s', async (_name, meta, settings, target) => {
     authStore.isAdmin = meta.requiresRiskControl === true
     appStore.cachedPublicSettings = settings
@@ -175,3 +178,35 @@ describe('feature route guard', () => {
     expect(next).toHaveBeenCalledWith(target)
   })
 })
+
+describe('subscription route guard (opt-out flag)', () => {
+  beforeEach(() => {
+    authStore.isAdmin = false
+    authStore.isSimpleMode = false
+    appStore.publicSettingsLoaded = true
+    appStore.fetchPublicSettings.mockReset()
+  })
+
+  it.each([
+    ['missing key', {}],
+    ['explicit true', { subscription_enabled: true }],
+  ])('lets /subscriptions through when the flag is %s', async (_name, settings) => {
+    appStore.cachedPublicSettings = settings
+
+    const { navigation, next } = runGuard({ requiresSubscription: true }, '/subscriptions')
+    await navigation
+
+    expect(next).toHaveBeenCalledOnce()
+    expect(next).toHaveBeenCalledWith()
+  })
+
+  it('sends admins to the admin dashboard when subscriptions are disabled', async () => {
+    authStore.isAdmin = true
+    appStore.cachedPublicSettings = { subscription_enabled: false }
+
+    const { navigation, next } = runGuard({ requiresSubscription: true }, '/subscriptions')
+    await navigation
+
+    expect(next).toHaveBeenCalledWith('/admin/dashboard')
+  })
+})

frontend/src/router/__tests__/title.spec.ts

@@ -1,5 +1,15 @@
-import { describe, expect, it } from 'vitest'
-import { resolveDocumentTitle, resolveRouteDocumentTitle } from '@/router/title'
+import { describe, expect, it, vi } from 'vitest'
+import { PURCHASE_ROUTE_NAME, resolveDocumentTitle, resolveRouteDocumentTitle, resolveRouteMetaKeys } from '@/router/title'
+
+// 语言包在测试环境是懒加载的，这里只提供本文件用到的几个 key，其余原样返回 key（触发 meta.title 回退）。
+vi.mock('@/i18n', () => {
+  const messages: Record<string, string> = {
+    'nav.recharge': '充值',
+    'nav.subscribe': '订阅',
+    'nav.buySubscription': '充值/订阅',
+  }
+  return { i18n: { global: { t: (key: string) => messages[key] ?? key } } }
+})
 
 describe('resolveDocumentTitle', () => {
   it('路由存在标题时，使用“路由标题 - 站点名”格式', () => {
@@ -47,3 +57,66 @@ describe('resolveRouteDocumentTitle', () => {
     ])).toBe('账号调度器 - EzouAPI')
   })
 })
+
+describe('resolveRouteMetaKeys', () => {
+  const purchaseRoute = {
+    name: PURCHASE_ROUTE_NAME,
+    meta: { titleKey: 'nav.buySubscription', descriptionKey: 'purchase.description' }
+  }
+
+  it('默认（充值 & 订阅或未知）沿用路由 meta 的标题/描述 key', () => {
+    expect(resolveRouteMetaKeys(purchaseRoute)).toEqual({
+      titleKey: 'nav.buySubscription',
+      descriptionKey: 'purchase.description'
+    })
+    expect(resolveRouteMetaKeys(purchaseRoute, { billingMode: 'recharge_and_subscription' })).toEqual({
+      titleKey: 'nav.buySubscription',
+      descriptionKey: 'purchase.description'
+    })
+  })
+
+  it('仅充值时 /purchase 切换为纯充值文案', () => {
+    expect(resolveRouteMetaKeys(purchaseRoute, { billingMode: 'recharge_only' })).toEqual({
+      titleKey: 'nav.recharge',
+      descriptionKey: 'purchase.rechargeDescription'
+    })
+  })
+
+  it('仅订阅时 /purchase 切换为纯订阅文案', () => {
+    expect(resolveRouteMetaKeys(purchaseRoute, { billingMode: 'subscription_only' })).toEqual({
+      titleKey: 'nav.subscribe',
+      descriptionKey: 'purchase.subscriptionDescription'
+    })
+  })
+
+  it('站点类型不影响其他路由', () => {
+    const route = { name: 'Subscriptions', meta: { titleKey: 'userSubscriptions.title' } }
+    expect(resolveRouteMetaKeys(route, { billingMode: 'recharge_only' })).toEqual({
+      titleKey: 'userSubscriptions.title',
+      descriptionKey: undefined
+    })
+  })
+})
+
+describe('resolveRouteDocumentTitle 站点类型', () => {
+  const purchaseRoute = {
+    name: PURCHASE_ROUTE_NAME,
+    params: {},
+    meta: { title: 'Purchase Subscription', titleKey: 'nav.buySubscription' }
+  }
+
+  it('仅充值时 document.title 不再带「订阅」', () => {
+    const title = resolveRouteDocumentTitle(purchaseRoute, 'EzouAPI', [], { billingMode: 'recharge_only' })
+    expect(title).toBe('充值 - EzouAPI')
+  })
+
+  it('仅订阅时 document.title 只剩「订阅」', () => {
+    const title = resolveRouteDocumentTitle(purchaseRoute, 'EzouAPI', [], { billingMode: 'subscription_only' })
+    expect(title).toBe('订阅 - EzouAPI')
+  })
+
+  it('充值 & 订阅时保留原标题', () => {
+    const title = resolveRouteDocumentTitle(purchaseRoute, 'EzouAPI', [], { billingMode: 'recharge_and_subscription' })
+    expect(title).toBe('充值/订阅 - EzouAPI')
+  })
+})

frontend/src/router/index.ts

@@ -297,7 +297,8 @@ const routes: RouteRecordRaw[] = [
       requiresAdmin: false,
       title: 'My Subscriptions',
       titleKey: 'userSubscriptions.title',
-      descriptionKey: 'userSubscriptions.description'
+      descriptionKey: 'userSubscriptions.description',
+      requiresSubscription: true
     }
   },
   {
@@ -907,7 +908,7 @@ router.beforeEach(async (to, _from, next) => {
   // 公共设置可能尚未加载（App.vue 的 onMounted 异步拉取晚于首次导航，且纯静态部署
   // 无 __APP_CONFIG__ 注入）。此时 cachedPublicSettings 为空会把 payment/risk_control
   // 误判为“未启用”而错误拦截，故这里先确保设置加载完成。
-  if ((to.meta.requiresPayment || to.meta.requiresRiskControl) && !appStore.publicSettingsLoaded) {
+  if ((to.meta.requiresPayment || to.meta.requiresRiskControl || to.meta.requiresSubscription) && !appStore.publicSettingsLoaded) {
     try {
       await appStore.fetchPublicSettings()
     } catch (error) {
@@ -935,6 +936,16 @@ router.beforeEach(async (to, _from, next) => {
     return
   }
 
+  // 订阅功能是 opt-out 开关：只有显式 false 才拦截「我的订阅」页直达。
+  if (
+    to.meta.requiresSubscription &&
+    appStore.publicSettingsLoaded &&
+    appStore.cachedPublicSettings?.subscription_enabled === false
+  ) {
+    next(authStore.isAdmin ? '/admin/dashboard' : '/dashboard')
+    return
+  }
+
   // 简易模式下限制访问某些页面
   if (authStore.isSimpleMode) {
     const restrictedPaths = [

frontend/src/router/meta.d.ts

@@ -55,6 +55,12 @@ declare module 'vue-router' {
      */
     requiresRiskControl?: boolean
 
+    /**
+     * 是否要求订阅功能开关（subscription_enabled，opt-out）未被显式关闭
+     * @default false
+     */
+    requiresSubscription?: boolean
+
     /**
      * i18n key for the page title
      */

frontend/src/router/title.ts

@@ -1,6 +1,7 @@
 import { i18n } from '@/i18n'
 import type { RouteLocationNormalizedLoaded } from 'vue-router'
 import type { CustomMenuItem } from '@/types'
+import type { SiteBillingMode } from '@/utils/siteBillingMode'
 
 /**
  * 统一生成页面标题，避免多处写入 document.title 产生覆盖冲突。
@@ -23,16 +24,56 @@ export function resolveDocumentTitle(routeTitle: unknown, siteName?: string, tit
   return normalizedSiteName
 }
 
+export interface RouteTitleOptions {
+  /**
+   * 站点计费模式（见 utils/billingMode.ts）。/purchase 的标题与描述随之切换：
+   * 仅充值 → 「充值」，仅订阅 → 「订阅」，缺省/两者都有 → 「充值/订阅」。
+   */
+  billingMode?: SiteBillingMode
+}
+
+export interface RouteMetaKeys {
+  titleKey?: string
+  descriptionKey?: string
+}
+
+/** /purchase 路由名，与 router/index.ts 中的声明保持一致。 */
+export const PURCHASE_ROUTE_NAME = 'PurchaseSubscription'
+
+/**
+ * 解析路由的 i18n 标题/描述 key。绝大多数路由直接取 meta；
+ * /purchase 随站点计费模式切换文案，AppHeader 与 document.title 共用这一处判断。
+ */
+export function resolveRouteMetaKeys(
+  route: Pick<RouteLocationNormalizedLoaded, 'name' | 'meta'>,
+  options: RouteTitleOptions = {},
+): RouteMetaKeys {
+  if (route.name === PURCHASE_ROUTE_NAME) {
+    if (options.billingMode === 'recharge_only') {
+      return { titleKey: 'nav.recharge', descriptionKey: 'purchase.rechargeDescription' }
+    }
+    if (options.billingMode === 'subscription_only') {
+      return { titleKey: 'nav.subscribe', descriptionKey: 'purchase.subscriptionDescription' }
+    }
+  }
+  return {
+    titleKey: typeof route.meta.titleKey === 'string' ? route.meta.titleKey : undefined,
+    descriptionKey: typeof route.meta.descriptionKey === 'string' ? route.meta.descriptionKey : undefined,
+  }
+}
+
 export function resolveRouteDocumentTitle(
   route: Pick<RouteLocationNormalizedLoaded, 'name' | 'params' | 'meta'>,
   siteName: string | undefined,
   customMenuItems: CustomMenuItem[] = [],
+  options: RouteTitleOptions = {},
 ): string {
   const id = typeof route.params.id === 'string' ? route.params.id : ''
   const menuItem = route.name === 'CustomPage' && id
     ? customMenuItems.find((item) => item.id === id)
     : undefined
   const menuTitle = menuItem?.label.trim()
+  const { titleKey } = resolveRouteMetaKeys(route, options)
 
-  return resolveDocumentTitle(menuTitle || route.meta.title, siteName, menuTitle ? undefined : route.meta.titleKey as string)
+  return resolveDocumentTitle(menuTitle || route.meta.title, siteName, menuTitle ? undefined : titleKey)
 }

frontend/src/stores/__tests__/app.spec.ts

@@ -55,6 +55,8 @@ function createPublicSettings(overrides: Partial<PublicSettings> = {}): PublicSe
     channel_monitor_enabled: true,
     channel_monitor_default_interval_seconds: 60,
     available_channels_enabled: false,
+    subscription_enabled: true,
+    payment_balance_disabled: false,
     model_plaza_enabled: false,
     model_plaza_require_auth: false,
     plugin_management_enabled: false,

frontend/src/stores/app.ts

@@ -371,6 +371,8 @@ export const useAppStore = defineStore('app', () => {
         channel_monitor_enabled: true,
         channel_monitor_default_interval_seconds: 60,
         available_channels_enabled: false,
+        subscription_enabled: true,
+        payment_balance_disabled: false,
         model_plaza_enabled: false,
         model_plaza_require_auth: false,
         plugin_management_enabled: false,

frontend/src/types/index.ts

@@ -276,6 +276,10 @@ export interface PublicSettings {
   /** When true, user monitor hides the user ranking tab and /users payload. */
   channel_monitor_hide_user_ranking?: boolean
   available_channels_enabled: boolean
+  /** When false, the whole user-facing subscription surface is hidden. Default true. */
+  subscription_enabled: boolean
+  /** Mirrors payment config BALANCE_PAYMENT_DISABLED; true = balance top-up closed (subscription-only site). */
+  payment_balance_disabled: boolean
   model_plaza_enabled: boolean
   model_plaza_require_auth: boolean
   plugin_management_enabled: boolean

frontend/src/utils/__tests__/featureFlags.spec.ts

@@ -0,0 +1,65 @@
+import { describe, it, expect, beforeEach, vi } from 'vitest'
+import { setActivePinia, createPinia } from 'pinia'
+import { useAppStore } from '@/stores/app'
+import { FeatureFlags, isFeatureFlagEnabled, makeSidebarFlag, resolveFeatureFlag } from '@/utils/featureFlags'
+import type { PublicSettings } from '@/types'
+
+vi.mock('@/api/admin/system', () => ({
+  checkUpdates: vi.fn(),
+}))
+
+vi.mock('@/api/auth', () => ({
+  getPublicSettings: vi.fn(),
+}))
+
+describe('FeatureFlags.subscription', () => {
+  beforeEach(() => {
+    setActivePinia(createPinia())
+    delete (window as any).__APP_CONFIG__
+  })
+
+  it('reads subscription_enabled as an opt-out flag: visible before settings load', () => {
+    expect(FeatureFlags.subscription.key).toBe('subscription_enabled')
+    expect(FeatureFlags.subscription.mode).toBe('opt-out')
+    expect(useAppStore().cachedPublicSettings).toBeNull()
+    expect(isFeatureFlagEnabled(FeatureFlags.subscription)).toBe(true)
+  })
+
+  it('hides only when the backend explicitly sends false', () => {
+    const store = useAppStore()
+    const sidebarFlag = makeSidebarFlag(FeatureFlags.subscription)
+
+    store.cachedPublicSettings = { subscription_enabled: false } as PublicSettings
+    expect(sidebarFlag()).toBe(false)
+
+    store.cachedPublicSettings = { subscription_enabled: true } as PublicSettings
+    expect(sidebarFlag()).toBe(true)
+
+    store.cachedPublicSettings = {} as PublicSettings
+    expect(sidebarFlag()).toBe(true)
+  })
+})
+
+describe('resolveFeatureFlag', () => {
+  beforeEach(() => {
+    setActivePinia(createPinia())
+  })
+
+  it('reads an explicit boolean from the given settings object', () => {
+    expect(resolveFeatureFlag({ subscription_enabled: false } as PublicSettings, FeatureFlags.subscription)).toBe(false)
+    expect(resolveFeatureFlag({ subscription_enabled: true } as PublicSettings, FeatureFlags.subscription)).toBe(true)
+    expect(resolveFeatureFlag({ available_channels_enabled: true } as PublicSettings, FeatureFlags.availableChannels)).toBe(true)
+  })
+
+  it('falls back to the declared mode when settings are missing or the key is absent', () => {
+    expect(resolveFeatureFlag(undefined, FeatureFlags.subscription)).toBe(true)
+    expect(resolveFeatureFlag(null, FeatureFlags.subscription)).toBe(true)
+    expect(resolveFeatureFlag({} as PublicSettings, FeatureFlags.subscription)).toBe(true)
+    expect(resolveFeatureFlag({} as PublicSettings, FeatureFlags.availableChannels)).toBe(false)
+  })
+
+  it('backs isFeatureFlagEnabled with the same resolution', () => {
+    useAppStore().cachedPublicSettings = { subscription_enabled: false } as PublicSettings
+    expect(isFeatureFlagEnabled(FeatureFlags.subscription)).toBe(false)
+  })
+})

frontend/src/utils/__tests__/siteBillingMode.spec.ts

@@ -0,0 +1,37 @@
+import { describe, it, expect } from 'vitest'
+import {
+  SITE_BILLING_MODES,
+  billingModeToSettings,
+  resolveSiteBillingMode,
+} from '@/utils/siteBillingMode'
+
+describe('resolveSiteBillingMode', () => {
+  it('defaults to recharge & subscription when settings are missing or empty', () => {
+    expect(resolveSiteBillingMode(undefined)).toBe('recharge_and_subscription')
+    expect(resolveSiteBillingMode(null)).toBe('recharge_and_subscription')
+    expect(resolveSiteBillingMode({})).toBe('recharge_and_subscription')
+  })
+
+  it('maps the two backend switches onto the three modes', () => {
+    expect(resolveSiteBillingMode({ subscription_enabled: true, payment_balance_disabled: false })).toBe('recharge_and_subscription')
+    expect(resolveSiteBillingMode({ subscription_enabled: false, payment_balance_disabled: false })).toBe('recharge_only')
+    expect(resolveSiteBillingMode({ subscription_enabled: true, payment_balance_disabled: true })).toBe('subscription_only')
+  })
+
+  it('treats the API-only "both disabled" combination as recharge only', () => {
+    expect(resolveSiteBillingMode({ subscription_enabled: false, payment_balance_disabled: true })).toBe('recharge_only')
+  })
+
+  it('round-trips every mode through billingModeToSettings', () => {
+    for (const mode of SITE_BILLING_MODES) {
+      expect(resolveSiteBillingMode(billingModeToSettings(mode))).toBe(mode)
+    }
+  })
+
+  it('never produces the both-disabled combination', () => {
+    for (const mode of SITE_BILLING_MODES) {
+      const settings = billingModeToSettings(mode)
+      expect(settings.subscription_enabled || !settings.payment_balance_disabled).toBe(true)
+    }
+  })
+})

frontend/src/utils/featureFlags.ts

@@ -104,6 +104,11 @@ export const FeatureFlags = {
     mode: 'opt-in',
     label: 'Available Channels',
   }),
+  subscription: defineFlag({
+    key: 'subscription_enabled',
+    mode: 'opt-out',
+    label: 'Subscription',
+  }),
   modelPlaza: defineFlag({
     key: 'model_plaza_enabled',
     mode: 'opt-in',
@@ -140,9 +145,19 @@ export type RegisteredFeatureFlag = keyof typeof FeatureFlags
  */
 export function isFeatureFlagEnabled(flag: FeatureFlagDefinition): boolean {
   const appStore = useAppStore()
-  const raw = appStore.cachedPublicSettings?.[flag.key] as
-    | boolean
-    | undefined
+  return resolveFeatureFlag(appStore.cachedPublicSettings, flag)
+}
+
+/**
+ * Pure resolver behind `isFeatureFlagEnabled`. Use it when the caller already
+ * holds a settings object (e.g. a store instance from `@/stores`) and should
+ * not reach for `useAppStore` itself — keeps views testable without Pinia.
+ */
+export function resolveFeatureFlag(
+  settings: Partial<PublicSettings> | null | undefined,
+  flag: FeatureFlagDefinition,
+): boolean {
+  const raw = settings?.[flag.key] as boolean | undefined
   if (typeof raw === 'boolean') return raw
   // Settings not yet loaded → fall back to the flag's declared mode:
   //   opt-out → visible by default, opt-in → hidden by default.

frontend/src/utils/siteBillingMode.ts

@@ -0,0 +1,50 @@
+import type { PublicSettings } from '@/types'
+import { FeatureFlags, resolveFeatureFlag } from '@/utils/featureFlags'
+
+/**
+ * 站点计费模式（后台「站点类型」单选），由两个后端开关派生：
+ * - `subscription_enabled`（opt-out，缺省视为开启）：用户端订阅面（侧边栏、购买页订阅 tab、顶栏徽章、/subscriptions）
+ * - `payment_balance_disabled`（strict true）：支付配置里的 BALANCE_PAYMENT_DISABLED，关闭余额充值下单
+ *
+ * 两者都关闭是接口层可表达但 UI 不提供的组合，这里归为「仅充值」；后台选择器保存时会把余额充值重新打开。
+ */
+export type SiteBillingMode = 'recharge_and_subscription' | 'recharge_only' | 'subscription_only'
+
+export const SITE_BILLING_MODES: readonly SiteBillingMode[] = [
+  'recharge_and_subscription',
+  'recharge_only',
+  'subscription_only',
+]
+
+/** i18n 子键（admin.settings.features.siteBillingMode.options / hints）。 */
+export const SITE_BILLING_MODE_I18N_KEYS: Record<SiteBillingMode, string> = {
+  recharge_and_subscription: 'rechargeAndSubscription',
+  recharge_only: 'rechargeOnly',
+  subscription_only: 'subscriptionOnly',
+}
+
+export interface BillingModeSettings {
+  subscription_enabled?: boolean
+  payment_balance_disabled?: boolean
+}
+
+export function resolveSiteBillingMode(settings: BillingModeSettings | null | undefined): SiteBillingMode {
+  const subscriptionEnabled = resolveFeatureFlag(
+    { subscription_enabled: settings?.subscription_enabled } as Partial<PublicSettings>,
+    FeatureFlags.subscription,
+  )
+  if (!subscriptionEnabled) return 'recharge_only'
+  if (settings?.payment_balance_disabled === true) return 'subscription_only'
+  return 'recharge_and_subscription'
+}
+
+export function billingModeToSettings(mode: SiteBillingMode): Required<BillingModeSettings> {
+  switch (mode) {
+    case 'recharge_only':
+      return { subscription_enabled: false, payment_balance_disabled: false }
+    case 'subscription_only':
+      return { subscription_enabled: true, payment_balance_disabled: true }
+    default:
+      return { subscription_enabled: true, payment_balance_disabled: false }
+  }
+}

frontend/src/views/KeyUsageView.vue

@@ -420,6 +420,7 @@
 import { ref, computed, onMounted, onUnmounted, nextTick } from 'vue'
 import { useI18n } from 'vue-i18n'
 import { useAppStore } from '@/stores'
+import { FeatureFlags, resolveFeatureFlag } from '@/utils/featureFlags'
 import LocaleSwitcher from '@/components/common/LocaleSwitcher.vue'
 import Icon from '@/components/icons/Icon.vue'
 import { buildGatewayUrl } from '@/api/client'
@@ -428,6 +429,7 @@ import { sanitizeUrl } from '@/utils/url'
 
 const { t, locale } = useI18n()
 const appStore = useAppStore()
+const subscriptionFeatureEnabled = computed(() => resolveFeatureFlag(appStore.cachedPublicSettings, FeatureFlags.subscription))
 
 // ==================== Site Settings (same as HomeView) ====================
 
@@ -728,7 +730,9 @@ const detailRows = computed<DetailRow[]>(() => {
   } else {
     rows.push({
       iconBg: 'bg-emerald-500/10', iconColor: 'text-emerald-500', iconSvg: ICON_CHECK,
-      label: t('keyUsage.subscriptionType'), value: data.planName || t('keyUsage.walletBalance'), valueClass: '',
+      // 订阅功能关闭后这一行只会是「钱包余额」，标签改用不带「订阅」字样的「计费方式」。
+      label: subscriptionFeatureEnabled.value ? t('keyUsage.subscriptionType') : t('keyUsage.billingType'),
+      value: data.planName || t('keyUsage.walletBalance'), valueClass: '',
     })
 
     if (data.subscription) {

frontend/src/views/__tests__/KeyUsageView.spec.ts

@@ -47,6 +47,7 @@ const messages: Record<string, string> = {
   'keyUsage.remainingQuota': 'Remaining Quota',
   'keyUsage.usedQuota': 'Used Quota',
   'keyUsage.subscriptionType': 'Subscription Type',
+  'keyUsage.billingType': 'Billing Type',
   'keyUsage.todayRequests': 'Today Requests',
   'keyUsage.todayInputTokens': 'Today Input',
   'keyUsage.todayOutputTokens': 'Today Output',
@@ -83,9 +84,15 @@ vi.mock('vue-i18n', async () => {
   }
 })
 
+const appStoreState = vi.hoisted(() => ({
+  cachedPublicSettings: null as Record<string, unknown> | null,
+}))
+
 vi.mock('@/stores', () => ({
   useAppStore: () => ({
-    cachedPublicSettings: null,
+    get cachedPublicSettings() {
+      return appStoreState.cachedPublicSettings
+    },
     siteName: 'Sub2API',
     siteLogo: '',
     docUrl: '',
@@ -232,3 +239,70 @@ describe('KeyUsageView daily detail', () => {
     wrapper.unmount()
   })
 })
+
+describe('KeyUsageView subscription feature flag', () => {
+  beforeEach(() => {
+    localStorage.clear()
+    Object.defineProperty(window, 'matchMedia', {
+      configurable: true,
+      value: vi.fn().mockReturnValue({ matches: false }),
+    })
+    vi.stubGlobal('requestAnimationFrame', (cb: FrameRequestCallback) => window.setTimeout(() => cb(0), 0))
+    vi.stubGlobal('fetch', vi.fn().mockResolvedValue({
+      ok: true,
+      json: async () => ({
+        mode: 'wallet',
+        isValid: true,
+        status: 'active',
+        balance: 5.5,
+        usage: {
+          today: { requests: 0, input_tokens: 0, output_tokens: 0, cache_creation_tokens: 0, cache_read_tokens: 0, total_tokens: 0, actual_cost: 0 },
+          total: { requests: 0, input_tokens: 0, output_tokens: 0, cache_creation_tokens: 0, cache_read_tokens: 0, total_tokens: 0, actual_cost: 0 },
+          rpm: 0,
+          tpm: 0,
+        },
+        daily_usage: [],
+      }),
+    }))
+  })
+
+  afterEach(() => {
+    appStoreState.cachedPublicSettings = null
+    vi.unstubAllGlobals()
+  })
+
+  async function mountAndQuery() {
+    const wrapper = mount(KeyUsageView, {
+      global: {
+        stubs: {
+          RouterLink: { template: '<a><slot /></a>' },
+          LocaleSwitcher: true,
+          Icon: true,
+        },
+      },
+    })
+    await wrapper.find('input').setValue('sk-test-key')
+    await wrapper.find('input').trigger('keydown.enter')
+    await flushPromises()
+    await nextTick()
+    return wrapper
+  }
+
+  it('labels the wallet row "Subscription Type" while subscriptions are enabled', async () => {
+    const wrapper = await mountAndQuery()
+
+    expect(wrapper.text()).toContain('Subscription Type')
+    expect(wrapper.text()).toContain('Wallet Balance')
+    wrapper.unmount()
+  })
+
+  it('drops the "Subscription" wording from the wallet row when subscriptions are disabled', async () => {
+    appStoreState.cachedPublicSettings = { subscription_enabled: false }
+    const wrapper = await mountAndQuery()
+
+    expect(wrapper.text()).toContain('Billing Type')
+    expect(wrapper.text()).not.toContain('Subscription Type')
+    expect(wrapper.text()).toContain('Wallet Balance')
+    wrapper.unmount()
+  })
+})

frontend/src/views/admin/SettingsView.vue

@@ -7227,6 +7227,36 @@
           </div>
         </div>
 
+        <div class="card">
+          <div class="border-b border-gray-100 px-6 py-4 dark:border-dark-700">
+            <h2 class="text-lg font-semibold text-gray-900 dark:text-white">
+              {{ t('admin.settings.features.siteBillingMode.title') }}
+            </h2>
+            <p class="mt-1 text-sm text-gray-500 dark:text-gray-400">
+              {{ t('admin.settings.features.siteBillingMode.description') }}
+            </p>
+          </div>
+          <div class="space-y-5 p-6">
+            <div class="flex flex-col gap-3 sm:flex-row sm:items-start sm:justify-between">
+              <div class="min-w-0">
+                <label class="text-sm font-medium text-gray-700 dark:text-gray-300">
+                  {{ t('admin.settings.features.siteBillingMode.label') }}
+                </label>
+                <p class="mt-0.5 text-xs text-gray-500 dark:text-gray-400">
+                  {{ siteBillingModeHint }}
+                </p>
+              </div>
+              <div class="w-full shrink-0 sm:w-56">
+                <Select
+                  :modelValue="siteBillingMode"
+                  :options="siteBillingModeOptions"
+                  @update:modelValue="siteBillingMode = $event as SiteBillingMode"
+                />
+              </div>
+            </div>
+          </div>
+        </div>
+
         <div class="card">
           <div class="border-b border-gray-100 px-6 py-4 dark:border-dark-700">
             <h2 class="text-lg font-semibold text-gray-900 dark:text-white">
@@ -8814,7 +8844,14 @@ import type {
 import type { ProviderInstance } from "@/types/payment";
 import AppLayout from "@/components/layout/AppLayout.vue";
 import Icon from "@/components/icons/Icon.vue";
-import Select from "@/components/common/Select.vue";
+import Select, { type SelectOption } from "@/components/common/Select.vue";
+import {
+  SITE_BILLING_MODES,
+  SITE_BILLING_MODE_I18N_KEYS,
+  billingModeToSettings,
+  resolveSiteBillingMode,
+  type SiteBillingMode,
+} from "@/utils/siteBillingMode";
 import ConfirmDialog from "@/components/common/ConfirmDialog.vue";
 import PaymentProviderList from "@/components/payment/PaymentProviderList.vue";
 import PaymentProviderDialog from "@/components/payment/PaymentProviderDialog.vue";
@@ -9814,6 +9851,8 @@ const form = reactive<SettingsForm>({
   channel_monitor_hide_user_ranking: false,
   // Available Channels feature switch
   available_channels_enabled: false,
+  // Subscription feature switch (user sidebar "My Subscriptions" entry)
+  subscription_enabled: true,
   // Model Plaza feature switches + description
   model_plaza_enabled: false,
   model_plaza_require_auth: false,
@@ -11021,6 +11060,24 @@ function findDuplicateDefaultSubscription(
   });
 }
 
+// 站点类型：由 subscription_enabled 与 payment_balance_disabled 两个开关派生的单选，
+// 保存时同时写回两者，避免出现「既无充值也无订阅」的组合。
+const siteBillingModeOptions = computed<SelectOption[]>(() =>
+  SITE_BILLING_MODES.map((mode) => ({
+    value: mode,
+    label: t(`admin.settings.features.siteBillingMode.options.${SITE_BILLING_MODE_I18N_KEYS[mode]}`),
+  })),
+);
+const siteBillingMode = computed<SiteBillingMode>({
+  get: () => resolveSiteBillingMode(form),
+  set: (mode) => {
+    Object.assign(form, billingModeToSettings(mode));
+  },
+});
+const siteBillingModeHint = computed(() =>
+  t(`admin.settings.features.siteBillingMode.hints.${SITE_BILLING_MODE_I18N_KEYS[siteBillingMode.value]}`),
+);
+
 async function saveSettings() {
   saving.value = true;
   try {
@@ -11478,6 +11535,8 @@ async function saveSettings() {
       channel_monitor_hide_user_ranking: Boolean(form.channel_monitor_hide_user_ranking),
       // Available Channels feature switch
       available_channels_enabled: form.available_channels_enabled,
+      // Subscription feature switch
+      subscription_enabled: form.subscription_enabled,
       // Model Plaza feature switches + description
       model_plaza_enabled: form.model_plaza_enabled,
       model_plaza_require_auth: form.model_plaza_require_auth,

frontend/src/views/user/PaymentView.vue

@@ -33,8 +33,12 @@
         </template>
         <!-- Tab content (select phase) -->
         <template v-else>
+          <!-- Neither top-up nor subscriptions available (balance recharge disabled via API while subscriptions are off) -->
+          <div v-if="tabs.length === 0" class="card py-16 text-center">
+            <p class="text-gray-500 dark:text-gray-400">{{ t('payment.billingUnavailable') }}</p>
+          </div>
           <!-- Top-up Tab -->
-          <template v-if="activeTab === 'recharge'">
+          <template v-else-if="activeTab === 'recharge'">
             <!-- Recharge Account Card -->
             <div class="card p-5">
               <p class="text-xs font-medium text-gray-400 dark:text-gray-500">{{ t('payment.rechargeAccount') }}</p>
@@ -266,6 +270,7 @@ import { useAuthStore } from '@/stores/auth'
 import { usePaymentStore } from '@/stores/payment'
 import { useSubscriptionStore } from '@/stores/subscriptions'
 import { useAppStore } from '@/stores'
+import { FeatureFlags, resolveFeatureFlag } from '@/utils/featureFlags'
 import { paymentAPI } from '@/api/payment'
 import { extractApiErrorMessage, extractI18nErrorMessage } from '@/utils/apiError'
 import { isMobileDevice } from '@/utils/device'
@@ -512,13 +517,26 @@ const renderedHelpText = computed(() => DOMPurify.sanitize(
   marked.parse(checkout.value.help_text || '', { async: false, gfm: true, breaks: false }),
 ))
 
+// 订阅功能开关（public settings 的 subscription_enabled，opt-out）。关闭后购买页只保留充值：
+// 不再渲染「订阅」tab，只剩单个 tab 时顶部切换器也随之隐藏。
+const subscriptionEnabled = computed(() => resolveFeatureFlag(appStore.cachedPublicSettings, FeatureFlags.subscription))
+
 const tabs = computed(() => {
   const result: { key: 'recharge' | 'subscription'; label: string }[] = []
   if (!checkout.value.balance_disabled) result.push({ key: 'recharge', label: t('payment.tabTopUp') })
-  result.push({ key: 'subscription', label: t('payment.tabSubscribe') })
+  if (subscriptionEnabled.value) result.push({ key: 'subscription', label: t('payment.tabSubscribe') })
   return result
 })
 
+// tab 列表随 checkout（balance_disabled）与订阅开关变化。当前 tab 不在列表里时收敛到第一个可用 tab，
+// 两个方向都覆盖：关闭订阅 → 回到充值；仅订阅站点重新打开订阅 → 进入订阅。列表为空时模板展示不可用提示。
+watch(tabs, (available) => {
+  if (available.some((tab) => tab.key === activeTab.value)) return
+  const leavingSubscription = activeTab.value === 'subscription'
+  activeTab.value = available[0]?.key ?? 'recharge'
+  if (leavingSubscription) selectedPlan.value = null
+})
+
 const visibleMethods = computed(() => getVisibleMethods(checkout.value.methods))
 const enabledMethods = computed(() => Object.keys(visibleMethods.value))
 const validAmount = computed(() => amount.value ?? 0)
@@ -1142,11 +1160,9 @@ onMounted(async () => {
       }
     }
     await resumeWechatPaymentFromQuery()
-    if (checkout.value.balance_disabled) {
-      activeTab.value = 'subscription'
-    }
-    // Handle renewal navigation: ?tab=subscription&group=123
-    if (route.query.tab === 'subscription') {
+    // balance_disabled → the tabs watcher above moves activeTab to the subscription tab (when enabled).
+    // Handle renewal navigation: ?tab=subscription&group=123 (ignored when subscriptions are disabled)
+    if (route.query.tab === 'subscription' && subscriptionEnabled.value) {
       activeTab.value = 'subscription'
       if (route.query.group) {
         const groupId = Number(route.query.group)
@@ -1161,7 +1177,9 @@ onMounted(async () => {
     }
   } catch (err: unknown) { appStore.showError(extractI18nErrorMessage(err, t, 'payment.errors', t('common.error'))) }
   finally { loading.value = false }
-  // Fetch active subscriptions (uses cache, non-blocking)
-  subscriptionStore.fetchActiveSubscriptions().catch(() => {})
+  // Fetch active subscriptions (uses cache, non-blocking); skipped when the subscription feature is off
+  if (subscriptionEnabled.value) {
+    subscriptionStore.fetchActiveSubscriptions().catch(() => {})
+  }
 })
 </script>

frontend/src/views/user/UsageView.vue

@@ -115,7 +115,7 @@
               <label class="input-label">{{ t('usage.compactionFilter') }}</label>
               <Select v-model="filters.native_compaction_v2" :options="compactionOptions" @change="applyFilters" />
             </div>
-            <div class="w-full sm:w-auto sm:min-w-[200px]">
+            <div v-if="subscriptionFeatureEnabled" class="w-full sm:w-auto sm:min-w-[200px]">
               <label class="input-label">{{ t('admin.usage.billingType') }}</label>
               <Select v-model="filters.billing_type" :options="billingTypeOptions" @change="applyFilters" />
             </div>
@@ -222,6 +222,7 @@
 import { computed, onMounted, onUnmounted, reactive, ref, watch } from 'vue'
 import { useI18n } from 'vue-i18n'
 import { useAppStore } from '@/stores/app'
+import { FeatureFlags, resolveFeatureFlag } from '@/utils/featureFlags'
 import { keysAPI, usageAPI, userGroupsAPI } from '@/api'
 import AppLayout from '@/components/layout/AppLayout.vue'
 import Pagination from '@/components/common/Pagination.vue'
@@ -391,6 +392,8 @@ const compactionOptions = computed<SelectOption[]>(() => [
   { value: null, label: t('usage.allCompactionTypes') },
   { value: true, label: t('usage.compactionOnly') },
 ])
+// 订阅功能关闭后只剩余额计费，「计费类型」筛选（余额/订阅）失去意义，整块隐藏。
+const subscriptionFeatureEnabled = computed(() => resolveFeatureFlag(appStore.cachedPublicSettings, FeatureFlags.subscription))
 const billingTypeOptions = computed<SelectOption[]>(() => [
   { value: null, label: t('admin.usage.allBillingTypes') },
   { value: 0, label: t('admin.usage.billingTypeBalance') },

frontend/src/views/user/__tests__/PaymentView.spec.ts

@@ -1,4 +1,4 @@
-import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 import { flushPromises, shallowMount } from '@vue/test-utils'
 import PaymentView from '../PaymentView.vue'
 import { PAYMENT_RECOVERY_STORAGE_KEY } from '@/components/payment/paymentFlow'
@@ -26,6 +26,11 @@ const showWarning = vi.hoisted(() => vi.fn())
 const getCheckoutInfo = vi.hoisted(() => vi.fn())
 const bridgeInvoke = vi.hoisted(() => vi.fn())
 const translate = vi.hoisted(() => vi.fn((key: string) => key))
+// Public settings live in a reactive holder so tests can flip feature flags after mount
+// and exercise the watchers that react to them.
+const appStoreState = vi.hoisted(() => ({
+  setPublicSettings: (_value: Record<string, unknown> | undefined) => {},
+}))
 
 vi.mock('vue-router', async () => {
   const actual = await vi.importActual<typeof import('vue-router')>('vue-router')
@@ -73,13 +78,23 @@ vi.mock('@/stores/subscriptions', () => ({
   }),
 }))
 
-vi.mock('@/stores', () => ({
-  useAppStore: () => ({
-    showError,
-    showInfo,
-    showWarning,
-  }),
-}))
+vi.mock('@/stores', async () => {
+  const { reactive } = await import('vue')
+  const state = reactive({ cachedPublicSettings: undefined as Record<string, unknown> | undefined })
+  appStoreState.setPublicSettings = (value) => {
+    state.cachedPublicSettings = value
+  }
+  return {
+    useAppStore: () => ({
+      showError,
+      showInfo,
+      showWarning,
+      get cachedPublicSettings() {
+        return state.cachedPublicSettings
+      },
+    }),
+  }
+})
 
 vi.mock('@/api/payment', () => ({
   paymentAPI: {
@@ -804,3 +819,71 @@ describe('PaymentView WeChat JSAPI flow', () => {
     expect(window.localStorage.getItem(PAYMENT_RECOVERY_STORAGE_KEY)).toContain('weixin://wxpay/bizpayurl?pr=fallback-native')
   })
 })
+
+describe('PaymentView subscription feature flag', () => {
+  afterEach(() => {
+    appStoreState.setPublicSettings(undefined)
+  })
+
+  function tabLabels(wrapper: Awaited<ReturnType<typeof mountSubscriptionPlanList>>) {
+    return wrapper
+      .findAll('button')
+      .map((button) => button.text())
+      .filter((text) => text === 'payment.tabTopUp' || text === 'payment.tabSubscribe')
+  }
+
+  it('keeps the top-up / subscribe switcher when subscription_enabled is absent (opt-out default)', async () => {
+    const wrapper = await mountSubscriptionPlanList(2)
+
+    expect(tabLabels(wrapper)).toEqual(['payment.tabTopUp', 'payment.tabSubscribe'])
+    expect(wrapper.findAllComponents(SubscriptionPlanCard)).toHaveLength(2)
+  })
+
+  it('drops the subscribe tab, hides the switcher and ignores ?tab=subscription when subscriptions are disabled', async () => {
+    appStoreState.setPublicSettings({ subscription_enabled: false })
+    const wrapper = await mountSubscriptionPlanList(2)
+
+    expect(tabLabels(wrapper)).toEqual([])
+    expect(wrapper.findAllComponents(SubscriptionPlanCard)).toHaveLength(0)
+    expect(wrapper.text()).toContain('payment.rechargeAccount')
+  })
+
+  it('shows an unavailable notice instead of a doomed top-up form when balance recharge is disabled too', async () => {
+    appStoreState.setPublicSettings({ subscription_enabled: false })
+    const wrapper = await mountSubscriptionConfirm({ checkout: { balance_disabled: true } })
+
+    expect(tabLabels(wrapper)).toEqual([])
+    expect(wrapper.findAllComponents(SubscriptionPlanCard)).toHaveLength(0)
+    expect(wrapper.text()).not.toContain('payment.confirmSubscription')
+    expect(wrapper.text()).not.toContain('payment.rechargeAccount')
+    expect(wrapper.text()).toContain('payment.billingUnavailable')
+    wrapper.unmount()
+  })
+
+  it('falls back from the subscribe tab to top-up when the flag flips off after mount', async () => {
+    const wrapper = await mountSubscriptionPlanList(2)
+    expect(wrapper.findAllComponents(SubscriptionPlanCard)).toHaveLength(2)
+
+    appStoreState.setPublicSettings({ subscription_enabled: false })
+    await flushPromises()
+
+    expect(tabLabels(wrapper)).toEqual([])
+    expect(wrapper.findAllComponents(SubscriptionPlanCard)).toHaveLength(0)
+    expect(wrapper.text()).toContain('payment.rechargeAccount')
+    wrapper.unmount()
+  })
+
+  it('enters the subscribe tab when a subscription-only site turns subscriptions back on', async () => {
+    appStoreState.setPublicSettings({ subscription_enabled: false })
+    const wrapper = await mountSubscriptionConfirm({ checkout: { balance_disabled: true } })
+    expect(wrapper.text()).toContain('payment.billingUnavailable')
+
+    appStoreState.setPublicSettings({ subscription_enabled: true })
+    await flushPromises()
+
+    expect(wrapper.text()).not.toContain('payment.billingUnavailable')
+    expect(wrapper.text()).not.toContain('payment.rechargeAccount')
+    expect(wrapper.findAllComponents(SubscriptionPlanCard).length).toBeGreaterThan(0)
+    wrapper.unmount()
+  })
+})

frontend/src/views/user/__tests__/UsageView.spec.ts

@@ -1,4 +1,4 @@
-import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 import { flushPromises, mount } from '@vue/test-utils'
 
 import UsageView from '../UsageView.vue'
@@ -89,10 +89,16 @@ vi.mock('@/api', () => ({
   },
 }))
 
+const appStoreState = vi.hoisted(() => ({
+  cachedPublicSettings: { allow_user_view_error_requests: true } as Record<string, unknown>,
+}))
+
 vi.mock('@/stores/app', () => ({
   useAppStore: () => ({
     showError, showWarning, showSuccess, showInfo,
-    cachedPublicSettings: { allow_user_view_error_requests: true },
+    get cachedPublicSettings() {
+      return appStoreState.cachedPublicSettings
+    },
   }),
 }))
 
@@ -460,3 +466,35 @@ describe('user UsageView', () => {
     clickSpy.mockRestore()
   })
 })
+
+describe('UsageView subscription feature flag', () => {
+  afterEach(() => {
+    appStoreState.cachedPublicSettings = { allow_user_view_error_requests: true }
+  })
+
+  function billingTypeSelect(wrapper: ReturnType<typeof mountUsageView>) {
+    return wrapper.findAllComponents(Select).find((select) =>
+      select.props('options').some((option: SelectOption) => option.label === 'Subscription')
+    )
+  }
+
+  it('offers the balance / subscription billing-type filter by default', async () => {
+    const wrapper = mountUsageView()
+    await flushPromises()
+
+    expect(billingTypeSelect(wrapper)).toBeDefined()
+    expect(wrapper.text()).toContain('Billing type')
+    wrapper.unmount()
+  })
+
+  it('hides the billing-type filter entirely when subscriptions are disabled', async () => {
+    appStoreState.cachedPublicSettings = { allow_user_view_error_requests: true, subscription_enabled: false }
+
+    const wrapper = mountUsageView()
+    await flushPromises()
+
+    expect(billingTypeSelect(wrapper)).toBeUndefined()
+    expect(wrapper.text()).not.toContain('Billing type')
+    wrapper.unmount()
+  })
+})