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/hooks/useFocusTrap.ts

@@ -0,0 +1,46 @@
+import { useEffect, useRef } from 'react';
+
+export const useFocusTrap = (isActive: boolean) => {
+  const containerRef = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    if (!isActive || !containerRef.current) return;
+
+    const container = containerRef.current;
+    const focusableElements = container.querySelectorAll(
+      'a[href], button:not([disabled]), textarea:not([disabled]), input:not([disabled]), select:not([disabled]), [tabindex]:not([tabindex="-1"])'
+    );
+    
+    const firstFocusable = focusableElements[0] as HTMLElement;
+    const lastFocusable = focusableElements[focusableElements.length - 1] as HTMLElement;
+
+    // Focus first element when trap is activated
+    firstFocusable?.focus();
+
+    const handleKeyDown = (e: KeyboardEvent) => {
+      if (e.key !== 'Tab') return;
+
+      if (e.shiftKey) {
+        // Shift + Tab
+        if (document.activeElement === firstFocusable) {
+          e.preventDefault();
+          lastFocusable?.focus();
+        }
+      } else {
+        // Tab
+        if (document.activeElement === lastFocusable) {
+          e.preventDefault();
+          firstFocusable?.focus();
+        }
+      }
+    };
+
+    container.addEventListener('keydown', handleKeyDown);
+
+    return () => {
+      container.removeEventListener('keydown', handleKeyDown);
+    };
+  }, [isActive]);
+
+  return containerRef;
+};

frontend/src/hooks/useOnClickOutside.ts

@@ -0,0 +1,24 @@
+import { useEffect, type RefObject } from 'react';
+
+export function useOnClickOutside<T extends HTMLElement = HTMLElement>(
+  ref: RefObject<T | null>,
+  handler: () => void
+) {
+  useEffect(() => {
+    const listener = (event: MouseEvent | TouchEvent) => {
+      // Do nothing if clicking ref's element or descendent elements
+      if (!ref.current || ref.current.contains(event.target as Node)) {
+        return;
+      }
+      handler();
+    };
+
+    document.addEventListener('mousedown', listener);
+    document.addEventListener('touchstart', listener);
+
+    return () => {
+      document.removeEventListener('mousedown', listener);
+      document.removeEventListener('touchstart', listener);
+    };
+  }, [ref, handler]);
+}