Fix navigation issues with ProtectedRoute

Fixed infinite redirect loop and navigation blocking in ProtectedRoute component. The issue was that the useEffect was running on every render when navigating between admin routes.

## Changes:
- Added hasChecked state to ensure effect only runs once per mount
- Prevents multiple redirects and navigation blocking
- Allows smooth navigation between admin and member pages after login

## Technical Details:
- Before: useEffect ran on every render with requireAdmin in dependencies
- After: useEffect runs once when auth loading completes
- This prevents React Router navigation conflicts

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

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/components/ProtectedRoute.tsx

@@ -1,4 +1,4 @@
-import { useEffect } from 'react';
+import { useEffect, useState } from 'react';
 import { useNavigate } from 'react-router-dom';
 import { useAuth } from '@/hooks/useAuth';
 import { Skeleton } from '@/components/ui/skeleton';
@@ -11,9 +11,13 @@ interface ProtectedRouteProps {
 export function ProtectedRoute({ children, requireAdmin = false }: ProtectedRouteProps) {
   const { user, loading: authLoading } = useAuth();
   const navigate = useNavigate();
+  const [hasChecked, setHasChecked] = useState(false);
 
   useEffect(() => {
-    if (!authLoading) {
+    // Only run effect once after auth loading completes
+    if (!authLoading && !hasChecked) {
+      setHasChecked(true);
+
       if (!user) {
         // Save current URL to redirect back after login
         const currentPath = window.location.pathname + window.location.search;
@@ -32,10 +36,10 @@ export function ProtectedRoute({ children, requireAdmin = false }: ProtectedRout
         }
       }
     }
-  }, [user, authLoading, navigate, requireAdmin]);
+  }, [user, authLoading, navigate, requireAdmin, hasChecked]);
 
   // Show loading skeleton while checking auth
-  if (authLoading) {
+  if (authLoading || !hasChecked) {
     return (
       <div className="min-h-screen bg-background">
         <div className="container mx-auto px-4 py-8">