feat: hide foreground webapp when switching sidebar pages

app/src/main/assets/h5/js/router.js

@@ -24,6 +24,15 @@ const router = {
     this.current = id;
     document.querySelectorAll('[data-page]').forEach(el =>
       el.classList.toggle('active', el.dataset.page === id));
+    // 切页时把前台 webapp 丢到后台（隐藏内容 WebView，标签状态保留）
+    // Hide the foreground webapp when switching pages (keep tab state)
+    bridge.call('hideWebApps').catch(() => {});
+    // 同时隐藏 webapp 顶栏与标签面板（离开 webapp 场景）
+    // Also hide the webapp topbar and tab panel (leaving the webapp context)
+    const topbar = document.getElementById('web-topbar');
+    if (topbar) topbar.style.display = 'none';
+    const tabPanel = document.getElementById('tab-panel');
+    if (tabPanel) tabPanel.style.display = 'none';
     // 非首页时侧边栏顶部显示小时间（容器始终占位，仅切换可见性避免撑动图标）
     // Show the small clock at the sidebar top when not on home (the container
     // always occupies space; only toggle visibility to avoid shifting icons)