feat(pwa): implement service worker and PWA enhancements

- Added service worker (sw.js) for offline functionality, caching strategies, and performance improvements.
- Registered service worker in App component to manage updates and offline readiness.
- Introduced ServiceWorkerStatus component to display connection status and provide cache management controls.
- Created manifest.json for PWA configuration, including app name, icons, and display settings.
- Updated index.html with PWA meta tags and links to support mobile web app capabilities.
- Refactored authentication guards to utilize useAuthStatus hook for improved user state management.
- Removed deprecated unregister-sw.js file to streamline service worker management.

worklenz-frontend/vite.config.ts

@@ -138,5 +138,8 @@ export default defineConfig(({ command, mode }) => {
     define: {
       __DEV__: !isProduction,
     },
+
+    // **Public Directory** - sw.js will be automatically copied from public/ to build/
+    publicDir: 'public',
   };
 });