feat(billing): Codex alpha/search 网页搜索按次计费

- alpha/search 成功请求（上游 2xx）按次计费落 usage_logs（billing_mode=per_request），
  上游错误透传/failover 不计费；使用 mandatory 池提交，池满同步兜底不丢扣费
- 单价默认 0.01 USD/次（官方 $10/1000 次），分组新增 web_search_price_per_call
  覆盖价（0=免费，负数/留空=默认价），实际扣费叠加分组费率倍数（与 token 口径一致）
- 分组字段全链路：ent schema + 迁移 174 + 端口快照 v15 + admin 创建/更新 + DTO
- 前端分组表单（openai 平台）新增单次价格配置，实时预览应用当前倍率后的单次价格
- 该端点鉴权维持仅 OpenAI 分组（非 OpenAI 分组 404）

frontend/src/views/admin/GroupsView.vue

@@ -1315,6 +1315,41 @@
           </div>
         </div>
 
+        <!-- Codex 网页搜索按次计费（仅 openai 平台） -->
+        <div
+          v-if="createForm.platform === 'openai'"
+          class="border-t border-gray-200 dark:border-dark-400 pt-4 mt-4"
+        >
+          <h4 class="text-sm font-medium text-gray-700 dark:text-gray-300 mb-3">
+            {{ t("admin.groups.webSearchPricing.title") }}
+          </h4>
+          <div>
+            <label class="input-label">{{
+              t("admin.groups.webSearchPricing.pricePerCall")
+            }}</label>
+            <input
+              v-model.number="createForm.web_search_price_per_call"
+              type="number"
+              step="0.001"
+              min="0"
+              placeholder="0.01"
+              class="input"
+            />
+            <p class="input-hint">
+              {{ t("admin.groups.webSearchPricing.pricePerCallHint") }}
+            </p>
+            <div
+              class="mt-2 rounded-lg bg-gray-50 p-3 text-xs text-gray-600 dark:bg-dark-700 dark:text-gray-300"
+            >
+              {{
+                t("admin.groups.webSearchPricing.finalPricePreview", {
+                  price: createWebSearchFinalPricePreview,
+                })
+              }}
+            </div>
+          </div>
+        </div>
+
         <!-- OpenAI Messages 调度配置（仅 openai 平台） -->
         <div
           v-if="createForm.platform === 'openai'"
@@ -2790,6 +2825,41 @@
           </div>
         </div>
 
+        <!-- Codex 网页搜索按次计费（仅 openai 平台） -->
+        <div
+          v-if="editForm.platform === 'openai'"
+          class="border-t border-gray-200 dark:border-dark-400 pt-4 mt-4"
+        >
+          <h4 class="text-sm font-medium text-gray-700 dark:text-gray-300 mb-3">
+            {{ t("admin.groups.webSearchPricing.title") }}
+          </h4>
+          <div>
+            <label class="input-label">{{
+              t("admin.groups.webSearchPricing.pricePerCall")
+            }}</label>
+            <input
+              v-model.number="editForm.web_search_price_per_call"
+              type="number"
+              step="0.001"
+              min="0"
+              placeholder="0.01"
+              class="input"
+            />
+            <p class="input-hint">
+              {{ t("admin.groups.webSearchPricing.pricePerCallHint") }}
+            </p>
+            <div
+              class="mt-2 rounded-lg bg-gray-50 p-3 text-xs text-gray-600 dark:bg-dark-700 dark:text-gray-300"
+            >
+              {{
+                t("admin.groups.webSearchPricing.finalPricePreview", {
+                  price: editWebSearchFinalPricePreview,
+                })
+              }}
+            </div>
+          </div>
+        </div>
+
         <!-- OpenAI Messages 调度配置（仅 openai 平台） -->
         <div
           v-if="editForm.platform === 'openai'"
@@ -3888,6 +3958,8 @@ const createForm = reactive({
   video_price_480p: null as number | null,
   video_price_720p: null as number | null,
   video_price_1080p: null as number | null,
+  // Codex 网页搜索按次计费（仅 openai 平台使用）；null = 使用默认价 0.01
+  web_search_price_per_call: null as number | null,
   // 高峰时段倍率配置
   peak_rate_enabled: false,
   peak_start: "",
@@ -4233,6 +4305,8 @@ const editForm = reactive({
   video_price_480p: null as number | null,
   video_price_720p: null as number | null,
   video_price_1080p: null as number | null,
+  // Codex 网页搜索按次计费（仅 openai 平台使用）；null = 使用默认价 0.01
+  web_search_price_per_call: null as number | null,
   // 高峰时段倍率配置
   peak_rate_enabled: false,
   peak_start: "",
@@ -4390,6 +4464,27 @@ const editVideoFinalPricePreview = computed(() =>
   buildVideoFinalPricePreview(editForm),
 );
 
+// Codex 网页搜索单次默认价（与后端 defaultWebSearchPricePerCall 一致，官方 $10/1000 次）
+const DEFAULT_WEB_SEARCH_PRICE_PER_CALL = 0.01;
+
+const buildWebSearchFinalPricePreview = (form: {
+  web_search_price_per_call: number | string | null;
+  rate_multiplier: number | string | null;
+}) => {
+  const basePrice =
+    parsePreviewPrice(form.web_search_price_per_call) ??
+    DEFAULT_WEB_SEARCH_PRICE_PER_CALL;
+  const multiplier = normalizePreviewNumber(form.rate_multiplier, 1);
+  return formatImagePricePreview(basePrice * multiplier);
+};
+
+const createWebSearchFinalPricePreview = computed(() =>
+  buildWebSearchFinalPricePreview(createForm),
+);
+const editWebSearchFinalPricePreview = computed(() =>
+  buildWebSearchFinalPricePreview(editForm),
+);
+
 const resetDisabledBatchImagePricing = (
   form: Pick<
     ImagePricingFormState,
@@ -4615,6 +4710,7 @@ const closeCreateModal = () => {
   createForm.video_price_480p = null;
   createForm.video_price_720p = null;
   createForm.video_price_1080p = null;
+  createForm.web_search_price_per_call = null;
   createForm.peak_rate_enabled = false;
   createForm.peak_start = "";
   createForm.peak_end = "";
@@ -4726,6 +4822,9 @@ const handleCreateGroup = async () => {
     requestData.video_price_480p = emptyToNull(requestData.video_price_480p);
     requestData.video_price_720p = emptyToNull(requestData.video_price_720p);
     requestData.video_price_1080p = emptyToNull(requestData.video_price_1080p);
+    requestData.web_search_price_per_call = emptyToNull(
+      requestData.web_search_price_per_call,
+    );
     requestData.peak_rate_enabled = createForm.peak_rate_enabled;
     requestData.peak_start = createForm.peak_start;
     requestData.peak_end = createForm.peak_end;
@@ -4779,6 +4878,7 @@ const handleEdit = async (group: AdminGroup) => {
   editForm.video_price_480p = group.video_price_480p;
   editForm.video_price_720p = group.video_price_720p;
   editForm.video_price_1080p = group.video_price_1080p;
+  editForm.web_search_price_per_call = group.web_search_price_per_call ?? null;
   editForm.peak_rate_enabled = group.peak_rate_enabled ?? false;
   editForm.peak_start = group.peak_start ?? "";
   editForm.peak_end = group.peak_end ?? "";
@@ -4836,6 +4936,7 @@ const closeEditModal = () => {
   editForm.video_price_480p = null;
   editForm.video_price_720p = null;
   editForm.video_price_1080p = null;
+  editForm.web_search_price_per_call = null;
   resetMessagesDispatchFormState(editForm);
   resetModelsListState(editModelsListState);
 };
@@ -4914,6 +5015,9 @@ const handleUpdateGroup = async () => {
     payload.video_price_480p = emptyPriceToClear(payload.video_price_480p);
     payload.video_price_720p = emptyPriceToClear(payload.video_price_720p);
     payload.video_price_1080p = emptyPriceToClear(payload.video_price_1080p);
+    payload.web_search_price_per_call = emptyPriceToClear(
+      payload.web_search_price_per_call,
+    );
     payload.peak_rate_enabled = editForm.peak_rate_enabled;
     payload.peak_start = editForm.peak_start;
     payload.peak_end = editForm.peak_end;