fix(player): 修复进度条拖动树稳定性

lib/pages/player/player_view.dart

@@ -304,11 +304,13 @@ class _PlayerPageState extends State<PlayerPage>
   }
 
   void _setScrubbing(bool value) {
+    if (!mounted) return;
     if (_scrubbing == value) return;
     setState(() => _scrubbing = value);
   }
 
   void _finishFeedScrub(bool wasVisible) {
+    if (!mounted) return;
     setState(() {
       _scrubbing = false;
       _chromeVisible = wasVisible;
@@ -322,6 +324,7 @@ class _PlayerPageState extends State<PlayerPage>
   }
 
   void _restoreFeedChrome() {
+    if (!mounted) return;
     setState(() {
       _scrubbing = false;
       _chromeVisible = true;

lib/pages/player/widgets/home_feed_overlay.dart

@@ -25,6 +25,7 @@ const double _railRight = 8;
 const double _railGap = 12;
 const double _bottomInfoInset = 32;
 const double _railBottomOffset = 60;
+const Duration _overlayFadeDuration = Duration(milliseconds: 120);
 const List<Shadow> _boostTextShadows = [
   Shadow(color: AppColors.shadow, blurRadius: 5, offset: Offset(0, 1)),
 ];
@@ -137,25 +138,46 @@ class _HomeFeedOverlayState extends State<HomeFeedOverlay> {
               ),
             ),
           ),
-          if (widget.boosting)
-            Positioned(left: 0, right: 0, bottom: 20, child: _boostHint())
-          else if (widget.visible && !_scrubbing)
-            Positioned(
-              left: _pageHorizontal,
-              right: _railRight,
-              bottom: _bottomInfoInset,
-              child: Row(
-                crossAxisAlignment: CrossAxisAlignment.end,
-                children: [
-                  Expanded(child: _bottomInfo()),
-                  const SizedBox(width: _railGap),
-                  Padding(
-                    padding: const EdgeInsets.only(bottom: _railBottomOffset),
-                    child: _rail(),
-                  ),
-                ],
+          Positioned(
+            left: _pageHorizontal,
+            right: _railRight,
+            bottom: _bottomInfoInset,
+            child: AnimatedOpacity(
+              key: const Key('home-feed-content-opacity'),
+              duration: _overlayFadeDuration,
+              opacity: widget.visible && !_scrubbing && !widget.boosting
+                  ? 1
+                  : 0,
+              child: IgnorePointer(
+                key: const Key('home-feed-content-ignore'),
+                ignoring: !widget.visible || _scrubbing || widget.boosting,
+                child: Row(
+                  crossAxisAlignment: CrossAxisAlignment.end,
+                  children: [
+                    Expanded(child: _bottomInfo()),
+                    const SizedBox(width: _railGap),
+                    Padding(
+                      padding: const EdgeInsets.only(bottom: _railBottomOffset),
+                      child: _rail(),
+                    ),
+                  ],
+                ),
               ),
             ),
+          ),
+          Positioned(
+            left: 0,
+            right: 0,
+            bottom: 20,
+            child: AnimatedOpacity(
+              duration: _overlayFadeDuration,
+              opacity: widget.boosting ? 1 : 0,
+              child: IgnorePointer(
+                ignoring: !widget.boosting,
+                child: _boostHint(),
+              ),
+            ),
+          ),
           Positioned(
             left: 0,
             right: 0,
@@ -177,6 +199,7 @@ class _HomeFeedOverlayState extends State<HomeFeedOverlay> {
   }
 
   void _startScrub() {
+    if (!mounted) return;
     _wasVisibleBeforeScrub = widget.visible;
     if (!_scrubbing) setState(() => _scrubbing = true);
     widget.onScrubVisibilityChanged?.call(true);
@@ -184,6 +207,7 @@ class _HomeFeedOverlayState extends State<HomeFeedOverlay> {
   }
 
   void _endScrub() {
+    if (!mounted) return;
     final wasVisible = _wasVisibleBeforeScrub;
     if (_scrubbing) setState(() => _scrubbing = false);
     widget.onScrubVisibilityChanged?.call(false);

lib/pages/player/widgets/home_feed_overlay_parts.dart

@@ -256,7 +256,7 @@ class _FeedProgressBarState extends State<_FeedProgressBar> {
   }
 
   void _startScrub(double fraction) {
-    if (_dragging) return;
+    if (!mounted || _dragging) return;
     setState(() {
       _dragging = true;
       _preview = fraction.clamp(0.0, 1.0).toDouble();
@@ -265,12 +265,12 @@ class _FeedProgressBarState extends State<_FeedProgressBar> {
   }
 
   void _update(double fraction) {
-    if (!_dragging) return;
+    if (!mounted || !_dragging) return;
     setState(() => _preview = fraction.clamp(0.0, 1.0).toDouble());
   }
 
   void _finishScrub() {
-    if (!_dragging) return;
+    if (!mounted || !_dragging) return;
     final fraction = _preview;
     setState(() {
       _dragging = false;