add: absorb uno-online as regular subdirectory

UNO card game web app (Node.js/React) with Miku bot integration.
Previously an independent git repo (fork of mizanxali/uno-online).
Removed .git/ and absorbed into main repo for unified tracking.

Includes bot integration code: botActionExecutor, cardParser,
gameStateBuilder, and server-side bot action support.
37 files, node_modules excluded via local .gitignore.

uno-online/client/src/index.js

@@ -0,0 +1,14 @@
+import React from 'react'
+import ReactDOM from 'react-dom'
+import './index.css'
+import App from './App'
+import { BrowserRouter } from 'react-router-dom'
+
+ReactDOM.render(
+  <React.StrictMode>
+    <BrowserRouter>
+      <App />
+    </BrowserRouter>
+  </React.StrictMode>,
+  document.getElementById('root')
+)