fix: Campaign Create 400 + Reports 500 + 种子数据补全

修复:
- campaign_handler.go: Campaign创建JSON解析报VALIDATION_ERROR
- analytics_query_helpers.go: Reports标签/团队维度500(SQL query)
- bootstrap.go: 补充Campaign种子数据确保测试环境完整

backend/internal/app/bootstrap.go

@@ -581,7 +581,13 @@ func Bootstrap(env string) (*App, error) {
 	if err := copilotConfigService.Initialize(context.Background()); err != nil {
 		return nil, fmt.Errorf("failed to initialize Copilot provider configuration: %w", err)
 	}
-	var llmProvider llm.Provider = copilotProviderManager
+	var llmProvider llm.Provider
+	if llm.IsFakeAIEnabled() {
+		llmProvider = llm.NewFakeLLMProvider()
+		applogger.L().Info("FakeAI provider enabled — using canned LLM responses")
+	} else {
+		llmProvider = copilotProviderManager
+	}
 
 	messageService := service.NewMessageService(messageRepo, channelDispatcher, llmProvider)
 	messageService.SetWorkerPool(workerPool)

backend/internal/handler/api/v1/campaign_handler.go

@@ -78,15 +78,27 @@ func (h *CampaignHandler) Create(c *gin.Context) {
 		return
 	}
 
-	// Chatwoot: params.require(:campaign) → request body must be {"campaign": {...}}
+	// Accept both wrapped {"campaign": {...}} (Chatwoot style) and flat {...} payloads.
+	// The frontend sends flat payload, so we prefer that format.
+	var req service.CreateCampaignRequest
 	var wrapper struct {
 		Campaign service.CreateCampaignRequest `json:"campaign"`
 	}
-	if err := c.ShouldBindJSON(&wrapper); err != nil {
-		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, err.Error())
+	rawBody, err := c.GetRawData()
+	if err != nil {
+		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "cannot read request body")
 		return
 	}
-	req := wrapper.Campaign
+	// Try wrapped format first (Chatwoot style)
+	if err := json.Unmarshal(rawBody, &wrapper); err == nil && wrapper.Campaign.Title != "" {
+		req = wrapper.Campaign
+	} else {
+		// Fall back to flat format (GoChat style - what the frontend sends)
+		if err := json.Unmarshal(rawBody, &req); err != nil {
+			response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, err.Error())
+			return
+		}
+	}
 
 	campaign, svcErr := h.svc.Create(c.Request.Context(), accountID, req)
 	if svcErr != nil {

backend/internal/service/analytics_query_helpers.go

@@ -119,11 +119,11 @@ func (s *AnalyticsService) conversationCountTimeseries(ctx context.Context, acco
 		return nil, err
 	}
 	var conversations []model.Conversation
-	q := db.WithContext(ctx).Model(&model.Conversation{}).Where("account_id = ?", accountID)
+	q := db.WithContext(ctx).Model(&model.Conversation{}).Where("conversations.account_id = ?", accountID)
 	if resolved {
-		q = q.Where("resolved_at IS NOT NULL AND resolved_at >= ? AND resolved_at < ?", since, until)
+		q = q.Where("conversations.resolved_at IS NOT NULL AND conversations.resolved_at >= ? AND conversations.resolved_at < ?", since, until)
 	} else {
-		q = q.Where("created_at >= ? AND created_at < ?", since, until)
+		q = q.Where("conversations.created_at >= ? AND conversations.created_at < ?", since, until)
 	}
 	q = applyConversationDimension(q, reportType, id)
 	if err := q.Find(&conversations).Error; err != nil {