feat: P7 在线播放（播放队列、媒体控制）与自建歌单

- 播放器：统一 PlayItem 队列，顺序 / 列表循环 / 单曲循环 / 随机，滚动歌词含翻译，Media Session，队列与进度存 localStorage
- 在线播放音质可在设置中选择；曲库已有的歌优先播放本地文件
- 自建歌单：混排在线曲目与本地文件，拖动排序，一键下载曲库缺失曲目

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/src/components/Icon.vue

@@ -30,6 +30,18 @@ const paths = {
   export: '<path d="M12 15V4m0 0L7.5 8.5M12 4l4.5 4.5M5 14v5.5h14V14"/>',
   plus: '<path d="M12 5v14M5 12h14"/>',
   logout: '<path d="M14 4.5H6.5v15H14M10.5 12H20m0 0-3.5-3.5M20 12l-3.5 3.5"/>',
+  prev: '<path d="M6.5 5.5v13"/><path d="M18.5 6.2v11.6L9.6 12z" fill="currentColor" stroke="none"/>',
+  next: '<path d="M17.5 5.5v13"/><path d="M5.5 6.2v11.6l8.9-5.8z" fill="currentColor" stroke="none"/>',
+  repeat: '<path d="M4.5 11.5v-1a3.5 3.5 0 0 1 3.5-3.5h11.5m0 0-3-3m3 3-3 3"/><path d="M19.5 12.5v1a3.5 3.5 0 0 1-3.5 3.5H4.5m0 0 3 3m-3-3 3-3"/>',
+  repeatOne: '<path d="M4.5 11.5v-1a3.5 3.5 0 0 1 3.5-3.5h11.5m0 0-3-3m3 3-3 3"/><path d="M19.5 12.5v1a3.5 3.5 0 0 1-3.5 3.5H4.5m0 0 3 3m-3-3 3-3"/><path d="m11 10.6 1.4-.9v4.6" stroke-width="1.4"/>',
+  shuffle: '<path d="M4 7h2.8c2 0 3.2 1 4.2 2.7l2.2 4.6c1 1.7 2.2 2.7 4.2 2.7H20m0 0-2.5-2.5M20 17l-2.5 2.5"/><path d="M4 17h2.8c1.3 0 2.2-.4 3-1.2m3.4-7.6c.8-.8 1.7-1.2 3-1.2H20m0 0-2.5-2.5M20 7l-2.5 2.5"/>',
+  order: '<path d="M4.5 7h10M4.5 12h10M4.5 17h6"/><path d="M18.5 8.5v10m0 0-2.5-2.5m2.5 2.5 2.5-2.5"/>',
+  queue: '<path d="M4 6.5h12M4 11h12M4 15.5h7"/><path d="M18.5 12.5v6.6"/><circle cx="16.6" cy="19.1" r="1.9"/><path d="M18.5 12.5l2.4 1.2"/>',
+  listPlus: '<path d="M4 6.5h12M4 11h12M4 15.5h7"/><path d="M17.5 13.5v7M14 17h7"/>',
+  playNext: '<path d="M4 6.5h12M4 11h9M4 15.5h7"/><path d="M15 13.6v6.8l5.4-3.4z" fill="currentColor" stroke="none"/>',
+  grip: '<circle cx="9.5" cy="7" r="1.15" fill="currentColor" stroke="none"/><circle cx="14.5" cy="7" r="1.15" fill="currentColor" stroke="none"/><circle cx="9.5" cy="12" r="1.15" fill="currentColor" stroke="none"/><circle cx="14.5" cy="12" r="1.15" fill="currentColor" stroke="none"/><circle cx="9.5" cy="17" r="1.15" fill="currentColor" stroke="none"/><circle cx="14.5" cy="17" r="1.15" fill="currentColor" stroke="none"/>',
+  edit: '<path d="M5 19l.9-3.9L15.6 5.4a1.8 1.8 0 0 1 2.6 0l.4.4a1.8 1.8 0 0 1 0 2.6L8.9 18.1z"/><path d="m13.8 7.2 3 3"/>',
+  mute: '<path d="M4.5 9.5h3l4.5-4v13l-4.5-4h-3z"/><path d="m15.5 9.5 5 5m0-5-5 5"/>',
 } as const;
 </script>