fix: grid minmax, media polling fallback, content webview layout, swipe timeout

app/src/main/java/top/yeij/hearth/MainActivity.kt

@@ -54,6 +54,10 @@ class MainActivity : Activity() {
         // 内容 WebView 顶栏预留高度（dp）
         // Topbar reserved height for content WebViews (dp)
         private const val TOPBAR_HEIGHT_DP = 44
+        // 全局侧边栏收起宽度（dp），内容 WebView 左侧预留，避免挡住侧边栏
+        // Global sidebar collapsed width (dp); content WebViews reserve it on the
+        // left to avoid covering the sidebar
+        private const val SIDEBAR_WIDTH_DP = 80
     }
 
     private val webAppContainer = WebAppContainer()
@@ -237,6 +241,9 @@ class MainActivity : Activity() {
         private val topBarHeightPx by lazy {
             (TOPBAR_HEIGHT_DP * resources.displayMetrics.density).toInt()
         }
+        private val sidebarWidthPx by lazy {
+            (SIDEBAR_WIDTH_DP * resources.displayMetrics.density).toInt()
+        }
 
         override fun openWebView(id: String, url: String) {
             if (contentWebViews.containsKey(id)) {
@@ -261,6 +268,7 @@ class MainActivity : Activity() {
                 ViewGroup.LayoutParams.MATCH_PARENT
             )
             params.topMargin = topBarHeightPx
+            params.leftMargin = sidebarWidthPx
             contentWebViews[id] = webView
             root.addView(webView, params)
             webView.loadUrl(url)