feat(server): implement chat file TTL cleanup and enhance JPush vendor channel support

Add FileCleanupWorker for automatic expiration of chat files with configurable retention period and batch processing. Files uploaded via `/api/v1/uploads/files` are tracked in `uploaded_files` table with expiration timestamps, then deleted from S3 and database upon expiry. Expired file URLs are injected as `"expired": true` in message responses.

Extend JPush push notification configuration with vendor-specific channel_id support (xiaomi, huawei, oppo, vivo, meizu, honor, fcm) for differentiating system vs chat notifications. Add iOS APNs thread-id grouping configuration for notification categorization.

internal/wire/handler.go

@@ -68,9 +68,10 @@ func ProvideMessageHandler(
 	messageService service.MessageService,
 	userService service.UserService,
 	groupService service.GroupService,
+	uploadService service.UploadService,
 	publisher ws.MessagePublisher,
 ) *handler.MessageHandler {
-	return handler.NewMessageHandler(chatService, messageService, userService, groupService, publisher)
+	return handler.NewMessageHandler(chatService, messageService, userService, groupService, uploadService, publisher)
 }
 
 // ProvideSystemMessageHandler 提供系统消息处理器