fix(recommend): 修正标题与观看全集跳转

lib/pages/player/widgets/seek_progress_bar.dart

@@ -171,11 +171,12 @@ class _SeekProgressBarState extends State<SeekProgressBar> {
   }
 
   Future<void> _finish(double fraction, Duration duration) async {
-    if (widget.locked || !_dragging) return;
+    final startedAt = _dragStartFraction;
+    _dragStartFraction = null;
+    if (widget.locked || !_dragging || startedAt == null) return;
     setState(() => _dragging = false);
     _pointerMoved = false;
     _pointerStart = null;
-    _dragStartFraction = null;
     widget.thumbnailService?.cancelPending();
     _previewFraction.value = null;
     widget.onScrubEnd?.call();