fix(flutter): 调整播放页底部信息排版

lib/pages/player/widgets/seek_progress_bar.dart

@@ -144,6 +144,8 @@ class _SeekProgressBarState extends State<SeekProgressBar> {
               label: widget.semanticsLabel,
               child: Slider(
                 value: fraction,
+                // 轨道与上方文案共用同一层水平内边距，避免 Slider 默认内缩。
+                padding: EdgeInsets.zero,
                 onChangeStart: enabled
                     ? (value) {
                         _previewFraction.value = value;