feat(player): 播放列表默认展开

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

my-uniapp-vue3/src/pages/player/index.vue

@@ -243,7 +243,7 @@ const showRatePicker = ref(false);
 const showTimerPicker = ref(false);
 const showSharePanel = ref(false);
 const showQualityPicker = ref(false);
-const showPlaylist = ref(false); // 播放列表展开/收起
+const showPlaylist = ref(true); // 播放列表展开/收起
 const savedProgress = ref(0); // 保存的历史进度
 const showResumePrompt = ref(false); // 显示继续播放提示
 const shareCard = ref({ title: '', description: '', imageUrl: '', link: '' });