Add ad-free YouTube player built on zero-native

Desktop YouTube player with no login and no ads. Extracts direct
video/audio streams with yt-dlp and plays them in a native window via
zero-native (Zig + system WebView) for a tiny footprint vs Electron.

- Dual-stream engine: muted video synced with separate audio track for
  high quality without ffmpeg muxing; progressive fallback
- On-device playlists, watch history, audio-only mode
- Full custom controls: seek, volume, speed, quality, fullscreen, queue
- Zig bridge handlers spawn yt-dlp and return slimmed JSON to the web UI
- Cinematic dark UI: Bricolage/Hanken/JetBrains Mono, vermilion accent

package.json

@@ -0,0 +1,11 @@
+{
+  "name": "ytplayer",
+  "version": "1.0.0",
+  "description": "Ad-free YouTube player with local playlists. No login, no ads, direct streams via yt-dlp. Built on zero-native (Zig + system WebView).",
+  "scripts": {
+    "setup": "node scripts/setup-ytdlp.js",
+    "update-ytdlp": "node scripts/setup-ytdlp.js --force"
+  },
+  "author": "",
+  "license": "MIT"
+}