add admin part

src/App.tsx

@@ -0,0 +1,19 @@
+import React from 'react';
+import { BrowserRouter as Router, Routes, Route } from 'react-router-dom';
+import AnnotationMain from './components/AnnotationMain/AnnotationMain';
+import Admin from './components/Admin/Admin.tsx';
+
+const App: React.FC = () => {
+    return (
+        <Router>
+            <div style={{ width: '100%', height: '100vh' }}> {/* Use full viewport height */}
+                <Routes>
+                    <Route path="/" element={<AnnotationMain />} />
+                    <Route path="/admin/*" element={<Admin />} />
+                </Routes>
+            </div>
+        </Router>
+    );
+};
+
+export default App;