Clean up: Remove src files

frontend/src/index.tsx

@@ -1,19 +0,0 @@
-import React from 'react';
-import ReactDOM from 'react-dom/client';
-import App from './App';
-import ErrorBoundary from './components/common/ErrorBoundary';
-import './index.css';
-
-const container = document.getElementById('root');
-
-if (!container) {
-  throw new Error('TaskFlow could not start: #root is missing from index.html');
-}
-
-ReactDOM.createRoot(container).render(
-  <React.StrictMode>
-    <ErrorBoundary>
-      <App />
-    </ErrorBoundary>
-  </React.StrictMode>
-);