Initial commit: Modern step-based UI for Rondevu demo

- Step-based flow: Choose action → Choose method → Enter details → Chat
- Modern design with clean header and footer
- GitHub links with icons to client and server repos
- Footer link to ronde.vu
- Three connection methods: Topic, Peer ID, Connection ID
- Real WebRTC peer-to-peer chat
- Mobile-responsive design
- Collapsible activity log

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/main.jsx

@@ -0,0 +1,10 @@
+import React from 'react';
+import ReactDOM from 'react-dom/client';
+import App from './App';
+import './index.css';
+
+ReactDOM.createRoot(document.getElementById('root')).render(
+  <React.StrictMode>
+    <App />
+  </React.StrictMode>
+);