fix(tray): use an app-specific tray id (#1978)

Co-authored-by: liyang <liyang25@pku.edu.cn>

src-tauri/src/commands/failover.rs

@@ -162,7 +162,7 @@ pub async fn set_auto_failover_enabled(
 
     // 刷新托盘菜单，确保状态同步
     if let Ok(new_menu) = crate::tray::create_tray_menu(&app, &state) {
-        if let Some(tray) = app.tray_by_id("main") {
+        if let Some(tray) = app.tray_by_id(crate::tray::TRAY_ID) {
             let _ = tray.set_menu(Some(new_menu));
         }
     }