Merge pull request #5938 from Hakunm/fix/google-one-model-catalog

fix(gemini): 限制 Google One OAuth 模型目录 / constrain Google One model catalog

backend/internal/handler/admin/account_handler.go

@@ -2614,8 +2614,14 @@ func (h *AccountHandler) GetAvailableModels(c *gin.Context) {
 
 	// Handle Gemini accounts
 	if account.IsGemini() {
-		// For OAuth accounts: return default Gemini models
+		// Consumer Google One OAuth still uses the legacy Gemini CLI / Code
+		// Assist channel. Do not advertise newer 3.x or image models that the
+		// channel cannot serve.
 		if account.IsOAuth() {
+			if account.IsGeminiGoogleOne() {
+				response.Success(c, geminicli.GoogleOneModels)
+				return
+			}
 			response.Success(c, geminicli.DefaultModels)
 			return
 		}

backend/internal/handler/admin/account_handler_available_models_test.go

@@ -287,6 +287,42 @@ func TestAccountHandlerGetAvailableModels_OpenAISparkShadowReturnsMappingModels(
 	}, ids, "影子可用模型由 model_mapping 派生（非写死）")
 }
 
+func TestAccountHandlerGetAvailableModels_GeminiGoogleOneUsesConservativeCatalog(t *testing.T) {
+	svc := &availableModelsAdminService{
+		stubAdminService: newStubAdminService(),
+		account: service.Account{
+			ID:       45,
+			Name:     "google-one",
+			Platform: service.PlatformGemini,
+			Type:     service.AccountTypeOAuth,
+			Status:   service.StatusActive,
+			Credentials: map[string]any{
+				"oauth_type": "google_one",
+			},
+		},
+	}
+	router := setupAvailableModelsRouter(svc)
+
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodGet, "/api/v1/admin/accounts/45/models", nil)
+	router.ServeHTTP(rec, req)
+
+	require.Equal(t, http.StatusOK, rec.Code)
+	var resp struct {
+		Data []struct {
+			ID string `json:"id"`
+		} `json:"data"`
+	}
+	require.NoError(t, json.Unmarshal(rec.Body.Bytes(), &resp))
+	ids := make([]string, 0, len(resp.Data))
+	for _, model := range resp.Data {
+		ids = append(ids, model.ID)
+	}
+	require.ElementsMatch(t, []string{"gemini-2.0-flash", "gemini-2.5-flash", "gemini-2.5-pro"}, ids)
+	require.NotContains(t, ids, "gemini-3.5-flash")
+	require.NotContains(t, ids, "gemini-2.5-flash-image")
+}
+
 func TestAccountHandlerSyncUpstreamModels_ConfigErrorReturnsBadRequest(t *testing.T) {
 	svc := &availableModelsAdminService{
 		stubAdminService: newStubAdminService(),