feat: structure

frontend/src/main.tsx

@@ -0,0 +1,24 @@
+import React from 'react'
+import ReactDOM from 'react-dom/client'
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
+import { ReactQueryDevtools } from '@tanstack/react-query-devtools'
+import App from './App'
+import './index.css'
+
+const queryClient = new QueryClient({
+  defaultOptions: {
+    queries: {
+      staleTime: 5 * 60 * 1000, // 5 minutes
+      retry: 2,
+    },
+  },
+})
+
+ReactDOM.createRoot(document.getElementById('root')!).render(
+  <React.StrictMode>
+    <QueryClientProvider client={queryClient}>
+      <App />
+      <ReactQueryDevtools initialIsOpen={false} />
+    </QueryClientProvider>
+  </React.StrictMode>,
+)