Updated files to have type support & enabled strict mode

src/App.tsx

@@ -1,6 +1,6 @@
 import React from 'react';
 
-function App() {
+function App() : JSX.Element {
   return (
     <div>
     </div>

src/index.tsx

@@ -1,8 +1,8 @@
+import App from './App';
 import React from 'react';
 import ReactDOM from 'react-dom/client';
-import App from './App';
 
-const root = ReactDOM.createRoot(
+const root : ReactDOM.Root = ReactDOM.createRoot(
   document.getElementById('root') as HTMLElement
 );
 

tsconfig.json

@@ -6,7 +6,7 @@
       "dom.iterable",
       "esnext"
     ],
-    "allowJs": true,
+    "allowJs": false,
     "skipLibCheck": true,
     "esModuleInterop": true,
     "allowSyntheticDefaultImports": true,