feat(frontend): HashRouter->BrowserRouter 干净URL可独立索引 + 静态预渲染(SSR注入#root/robots/sitemap) + logo回顶

frontend/src/main.tsx

@@ -1,13 +1,13 @@
 import React from 'react';
 import ReactDOM from 'react-dom/client';
-import { HashRouter } from 'react-router-dom';
+import { BrowserRouter } from 'react-router-dom';
 import App from './App';
 import './styles/global.css';
 
 ReactDOM.createRoot(document.getElementById('root')!).render(
   <React.StrictMode>
-    <HashRouter>
+    <BrowserRouter>
       <App />
-    </HashRouter>
+    </BrowserRouter>
   </React.StrictMode>
 );