feat(admin): 独立后台壳、站点分析与聊天监管，公开站拆出主题切换与访问埋点

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/handler/handlers.go

@@ -28,6 +28,8 @@ type Handlers struct {
 	AdminUser    *service.AdminUserService
 	Moderation   *service.ModerationService
 	Chat         *service.ChatService
+	Telemetry    *service.TelemetryService
+	Analytics    *service.AnalyticsService
 }
 
 // resolvePublishStatus 决定新帖/新评的初始状态：