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/tailwind.config.js

@@ -48,6 +48,7 @@ export default {
         'fade-in': 'fadeIn 0.5s ease-in-out',
         'slide-up': 'slideUp 0.3s ease-out',
         'scale-in': 'scaleIn 0.2s ease-out',
+        'shimmer': 'shimmer 2s cubic-bezier(0.4, 0, 0.6, 1) infinite',
       },
       keyframes: {
         fadeIn: {
@@ -62,6 +63,10 @@ export default {
           '0%': { transform: 'scale(0.95)', opacity: '0' },
           '100%': { transform: 'scale(1)', opacity: '1' },
         },
+        shimmer: {
+          '0%': { backgroundPosition: '-200% 0' },
+          '100%': { backgroundPosition: '200% 0' },
+        },
       },
       spacing: {
         '18': '4.5rem',