feat: 관리자 페이지 모바일 반응형 사이드바 토글 추가

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/admin/components/AdminShell.tsx

@@ -0,0 +1,49 @@
+'use client';
+
+import { useState } from 'react';
+import AdminSidebar from './AdminSidebar';
+
+export default function AdminShell({ children }: { children: React.ReactNode }) {
+  const [sidebarOpen, setSidebarOpen] = useState(false);
+
+  return (
+    <div className="flex h-screen bg-slate-950 overflow-hidden">
+      {/* 모바일 오버레이 */}
+      {sidebarOpen && (
+        <div
+          className="fixed inset-0 z-20 bg-black/60 lg:hidden"
+          onClick={() => setSidebarOpen(false)}
+        />
+      )}
+
+      <AdminSidebar isOpen={sidebarOpen} onClose={() => setSidebarOpen(false)} />
+
+      <div className="flex-1 flex flex-col overflow-hidden min-w-0">
+        {/* 모바일 상단 헤더 */}
+        <header className="lg:hidden flex items-center justify-between px-4 py-3 bg-slate-900 border-b border-slate-700/60 flex-shrink-0">
+          <button
+            onClick={() => setSidebarOpen(true)}
+            className="p-2 rounded-lg text-slate-400 hover:text-white hover:bg-slate-800 transition"
+            aria-label="메뉴 열기"
+          >
+            <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M4 6h16M4 12h16M4 18h16" />
+            </svg>
+          </button>
+          <div className="flex items-center gap-2">
+            <div className="w-8 h-8 rounded-xl bg-gradient-to-br from-red-500 to-orange-500 flex items-center justify-center text-white font-bold text-sm">
+              관
+            </div>
+            <span className="text-white font-bold text-sm">관리자 패널</span>
+          </div>
+          <div className="w-9" />
+        </header>
+
+        {/* 메인 스크롤 영역 */}
+        <main className="flex-1 overflow-y-auto">
+          {children}
+        </main>
+      </div>
+    </div>
+  );
+}