feat(webdav): follow-up 补齐自动同步与大文件防护 (#1043)

* feat(webdav): add robust auto sync with failure feedback

(cherry picked from commit bb6760124a62a964b36902c004e173534910728f)

* fix(webdav): enforce bounded download and extraction size

(cherry picked from commit 7777d6ec2b9bba07c8bbba9b04fe3ea6b15e0e79)

* fix(webdav): only show auto-sync callout for auto-source errors

* refactor(webdav): remove services->commands auto-sync dependency

src-tauri/src/lib.rs

@@ -702,6 +702,10 @@ pub fn run() {
             }
 
             let _tray = tray_builder.build(app)?;
+            crate::services::webdav_auto_sync::start_worker(
+                app_state.db.clone(),
+                app.handle().clone(),
+            );
             // 将同一个实例注入到全局状态，避免重复创建导致的不一致
             app.manage(app_state);