Feature: Add PR review comments and resolution, improve AI prompt handling (#790)

* feat: Add PR review comments and resolution endpoints, improve prompt handling

* Feature: File Editor (#789)

* feat: Add file management feature

* feat: Add auto-save functionality to file editor

* fix: Replace HardDriveDownload icon with Save icon for consistency

* fix: Prevent recursive copy/move and improve shell injection prevention

* refactor: Extract editor settings form into separate component

* ```
fix: Improve error handling and stabilize async operations

- Add error event handlers to GraphQL process spawns to prevent unhandled rejections
- Replace execAsync with execFile for safer command execution and better control
- Fix timeout cleanup in withTimeout generator to prevent memory leaks
- Improve outdated comment detection logic by removing redundant condition
- Use resolveModelString for consistent model string handling
- Replace || with ?? for proper falsy value handling in dialog initialization
- Add comments clarifying branch name resolution logic for local branches with slashes
- Add catch handler for project selection to handle async errors gracefully
```

* refactor: Extract PR review comments logic to dedicated service

* fix: Improve robustness and UX for PR review and file operations

* fix: Consolidate exec utilities and improve type safety

* refactor: Replace ScrollArea with div and improve file tree layout

apps/ui/src/renderer.tsx

@@ -1,6 +1,7 @@
 import { StrictMode } from 'react';
 import { createRoot } from 'react-dom/client';
 import App from './app';
+import { AppErrorBoundary } from './components/ui/app-error-boundary';
 import { isMobileDevice, isPwaStandalone } from './lib/mobile-detect';
 
 // Defensive fallback: index.html's inline script already applies data-pwa="standalone"
@@ -250,8 +251,12 @@ function warmAssetCache(registration: ServiceWorkerRegistration): void {
 }
 
 // Render the app - prioritize First Contentful Paint
+// AppErrorBoundary catches uncaught React errors and shows a friendly error screen
+// instead of TanStack Router's default "Something went wrong!" overlay.
 createRoot(document.getElementById('app')!).render(
   <StrictMode>
-    <App />
+    <AppErrorBoundary>
+      <App />
+    </AppErrorBoundary>
   </StrictMode>
 );