- feat(vscode-sync): restore auto-sync logic and enable by default

- refactor(settings): remove the VS Code auto-sync toggle from Settings UI
- feat(provider-list): enable auto-sync after "Apply to VS Code"; disable after "Remove"
- chore(prettier): run Prettier on changed files
- verify: typecheck and renderer build pass

- Files
  - added: src/hooks/useVSCodeAutoSync.ts
  - modified: src/App.tsx
  - modified: src/components/ProviderList.tsx
  - modified: src/components/SettingsModal.tsx

- Notes
  - Auto-sync now defaults to enabled for new users (stored in localStorage; existing saved state is respected).
  - No settings toggle is shown; manual Apply/Remove in the list still works as before.

src/App.tsx

@@ -114,7 +114,7 @@ function App() {
         unlisten();
       }
     };
-  }, [activeApp, isAutoSyncEnabled]); // 依赖自动同步状态，确保拿到最新开关
+  }, [activeApp, isAutoSyncEnabled]);
 
   const loadProviders = async () => {
     const loadedProviders = await window.api.getProviders(activeApp);
@@ -183,7 +183,7 @@ function App() {
     });
   };
 
-  // 同步Codex供应商到VS Code设置
+  // 同步Codex供应商到VS Code设置（静默覆盖）
   const syncCodexToVSCode = async (providerId: string, silent = false) => {
     try {
       const status = await window.api.getVSCodeSettingsStatus();