优化: 多模块功能修复与体验改进 (#34)

1. 保留策略清理后自动删除空文件夹（新增 StorageDirCleaner 接口）
2. 备份任务删除时清理远端文件但保留备份记录
3. 节点管理修复：本机 IP/版本检测、Heartbeat OS/Arch 修正、新增编辑功能
4. 审计日志规范化：统一格式、丰富详情、节点操作增加审计记录
5. 系统设置移除一键更新操作，仅保留版本检查
6. Rclone 配置项分层展示（必填 + 高级可选折叠）
7. DirectoryPicker 目录选择器样式优化

server/internal/app/app.go

@@ -79,6 +79,7 @@ func New(ctx context.Context, cfg config.Config, version string) (*Application,
 	storageTargetService.SetBackupTaskRepository(backupTaskRepo)
 	storageTargetService.SetBackupRecordRepository(backupRecordRepo)
 	backupTaskService := service.NewBackupTaskService(backupTaskRepo, storageTargetRepo, configCipher)
+	backupTaskService.SetRecordsAndStorage(backupRecordRepo, storageRegistry)
 	backupRunnerRegistry := backup.NewRegistry(backup.NewFileRunner(), backup.NewSQLiteRunner(), backup.NewMySQLRunner(nil), backup.NewPostgreSQLRunner(nil), backup.NewSAPHANARunner(nil))
 	logHub := backup.NewLogHub()
 	retentionService := backupretention.NewService(backupRecordRepo)
@@ -110,7 +111,7 @@ func New(ctx context.Context, cfg config.Config, version string) (*Application,
 
 	// Cluster: Node management
 	nodeRepo := repository.NewNodeRepository(db)
-	nodeService := service.NewNodeService(nodeRepo)
+	nodeService := service.NewNodeService(nodeRepo, version)
 	if err := nodeService.EnsureLocalNode(ctx); err != nil {
 		appLogger.Warn("failed to ensure local node", zap.Error(err))
 	}