fix: 软刷新齐套前保留旧画面，避免一点击就卸光

Logo/下拉静默预热后一次覆盖；commit 不再先 reset/loading；顺带会话预取与可配置 Feed 排序标签。

frontend/src/main.tsx

@@ -2,11 +2,21 @@ import React from 'react';
 import ReactDOM from 'react-dom/client';
 import { applyTheme, getStoredTheme } from './utils/theme';
 import App from './App';
+import { ensureColdBootReady, isMainLayoutPath } from './utils/prefetchRoute';
 
 applyTheme(getStoredTheme());
 
-ReactDOM.createRoot(document.getElementById('root')!).render(
-  <React.StrictMode>
-    <App />
-  </React.StrictMode>
-);
+async function boot() {
+  const path = `${window.location.pathname}${window.location.search}`;
+  // 前台：齐套前不挂载；完成后一次 createRoot
+  if (isMainLayoutPath(window.location.pathname)) {
+    await ensureColdBootReady(path);
+  }
+  ReactDOM.createRoot(document.getElementById('root')!).render(
+    <React.StrictMode>
+      <App />
+    </React.StrictMode>,
+  );
+}
+
+void boot();