feat(fullscreen): performance fixes + appearance settings

Adds no_compositing_mode Tauri command; frontend adds html.no-compositing on Linux to replace GPU-only CSS effects (backdrop-filter, filter, mask-image) with software-friendly equivalents.

Settings → Appearance → Fullscreen Player: toggle for artist portrait visibility + 0–80% dimming slider.

Fix: long words in lyric lines now wrap correctly.

src/locales/zh.ts

@@ -608,6 +608,10 @@ export const zhTranslation = {
     infiniteQueue: '无限队列',
     infiniteQueueDesc: '队列播完时自动追加随机曲目',
     experimental: '实验性',
+    fsPlayerSection: '全屏播放器',
+    fsShowArtistPortrait: '显示艺术家照片',
+    fsShowArtistPortraitDesc: '在全屏播放器右侧显示艺术家照片（或专辑封面）。',
+    fsPortraitDim: '照片暗化',
     seekbarStyle: '进度条样式',
     seekbarStyleDesc: '选择播放进度条的外观',
     seekbarWaveform: '波形',