feat: react template

cmd/templates/create-react-app/frontend/src/App.js

@@ -0,0 +1,21 @@
+import React from 'react';
+import logo from './logo.png';
+import './App.css';
+import HelloWorld from './components/HelloWorld';
+
+function App() {
+  return (
+    <div id="app" className="App">
+      <header className="App-header">
+        <img src={logo} className="App-logo" alt="logo" />
+        <p>
+          Welcome to your new <code>wails/react</code> project.
+        </p>
+
+        <HelloWorld />
+      </header>
+    </div>
+  );
+}
+
+export default App;