fix(task): restore task metadata contract and type fields in task types api

backend/plugins/domain/admin/plugin.go

@@ -171,9 +171,23 @@ func (p *Plugin) Apply(ctx *core.Context) error {
 	handler.RegisterRoutes(adminRouter)
 
 	// 2. Register Background Tasks
+	logSwitchHandler := &service.LogDBSwitchHandler{}
+	ctx.Task().Register(service.LogDBSwitchTask, func(c context.Context, payload []byte) error {
+		_, err := logSwitchHandler.Execute(c, payload)
+		return err
+	}, extpoints.WithTaskMeta(service.LogDBSwitchMeta))
+
 	ctx.Task().Register("admin:system_cleanup", func(_ context.Context, _ []byte) error {
 		return nil
-	}, extpoints.WithTaskRetry(1))
+	},
+		extpoints.WithTaskType("system_cleanup"),
+		extpoints.WithTaskName("系统垃圾清理"),
+		extpoints.WithTaskDescription("定期清理未使用上传文件、历史推送记录和过期任务执行日志"),
+		extpoints.WithTaskCategory("maintenance"),
+		extpoints.WithTaskRetry(1),
+		extpoints.WithTaskQueue("default"),
+		extpoints.WithTaskRetryable(true),
+	)
 
 	// 3. Register Cron Schedules
 	ctx.Schedule().RegisterCron("0 4 * * *", "admin:system_cleanup", map[string]string{"type": "daily"})