feat: restrict admin access to club operations and rollout test environment

frontend/src/app/(protected)/layout.tsx

@@ -1,13 +1,19 @@
+'use client';
+
 import { AuthGuard } from '@/components/auth-guard';
 import { ClubSwitcher } from '@/components/club-switcher';
 import Link from 'next/link';
 import { SignOutButton } from '@/components/sign-out-button';
+import { useSession } from 'next-auth/react';
 
 export default function ProtectedLayout({
   children,
 }: {
   children: React.ReactNode;
 }) {
+  const { data } = useSession();
+  const isAdmin = (data?.user as any)?.isAdmin;
+
   return (
     <AuthGuard>
       <div className="flex min-h-screen bg-gray-50">
@@ -15,26 +21,34 @@ export default function ProtectedLayout({
           <div className="p-4 border-b">
             <h1 className="text-xl font-bold">WorkClub</h1>
           </div>
-          <nav className="flex-1 p-4 space-y-2">
-            <Link href="/dashboard" className="flex items-center px-4 py-2 text-sm font-medium rounded-md hover:bg-gray-100">
-              Dashboard
-            </Link>
-            <Link href="/tasks" className="flex items-center px-4 py-2 text-sm font-medium rounded-md hover:bg-gray-100">
-              Tasks
-            </Link>
-            <Link href="/shifts" className="flex items-center px-4 py-2 text-sm font-medium rounded-md hover:bg-gray-100">
-              Shifts
-            </Link>
-            <Link href="/members" className="flex items-center px-4 py-2 text-sm font-medium rounded-md hover:bg-gray-100">
-              Members
-            </Link>
-          </nav>
+          {isAdmin ? (
+            <nav className="flex-1 p-4 space-y-2">
+              <Link href="/admin/clubs" className="flex items-center px-4 py-2 text-sm font-medium rounded-md hover:bg-gray-100">
+                Club Management
+              </Link>
+            </nav>
+          ) : (
+            <nav className="flex-1 p-4 space-y-2">
+              <Link href="/dashboard" className="flex items-center px-4 py-2 text-sm font-medium rounded-md hover:bg-gray-100">
+                Dashboard
+              </Link>
+              <Link href="/tasks" className="flex items-center px-4 py-2 text-sm font-medium rounded-md hover:bg-gray-100">
+                Tasks
+              </Link>
+              <Link href="/shifts" className="flex items-center px-4 py-2 text-sm font-medium rounded-md hover:bg-gray-100">
+                Shifts
+              </Link>
+              <Link href="/members" className="flex items-center px-4 py-2 text-sm font-medium rounded-md hover:bg-gray-100">
+                Members
+              </Link>
+            </nav>
+          )}
         </aside>
 
         <div className="flex-1 flex flex-col">
           <header className="bg-white border-b h-16 flex items-center justify-between px-6">
             <div className="flex items-center gap-4">
-              <ClubSwitcher />
+              {!isAdmin && <ClubSwitcher />}
             </div>
             <div className="flex items-center gap-4">
               <SignOutButton />