Expand README with architecture and setup details

src/main.tsx

@@ -0,0 +1,11 @@
+import React from 'react';
+import { createRoot } from 'react-dom/client';
+import { App } from './app/App';
+import './styles/app.css';
+
+createRoot(document.getElementById('root') as HTMLElement).render(
+  <React.StrictMode>
+    <App />
+  </React.StrictMode>,
+);
+