Implement complete frontend with admin panel and theme system

- Add admin authentication and dashboard
- Create event management pages (list, create, edit, archive)
- Implement gallery enhancements (search, sorting, bulk download)
- Add email configuration and archive management pages
- Integrate Umami analytics with tracking throughout the app
- Add comprehensive error boundaries and loading states
- Implement accessibility features (WCAG 2.1 AA compliance)
- Create theme system with preset themes and customization
- Add branding settings and company information management
- Fix backend database initialization and health check
- Configure proper API URLs and environment variables

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

frontend/src/components/common/index.ts

@@ -1,4 +1,8 @@
 export { Button } from './Button';
 export { Input } from './Input';
 export { Card, CardHeader, CardContent, CardFooter } from './Card';
-export { Loading, LoadingSkeleton } from './Loading';
+export { Loading, LoadingSkeleton } from './Loading';
+export * from './ErrorBoundary';
+export * from './Skeleton';
+export * from './OfflineIndicator';
+export * from './SkipLink';