Register devices and report verified holdings to the server

frontend/app.js

@@ -353,6 +353,8 @@ function toAssetUrl(path) {
 // ---------- State ----------
 const DEFAULT_SETTINGS = {
   quality: 'auto', volume: 1, audioOnly: false, autoPreload: true,
+  p2pShare: true,           // P2P (docs/p2p-architecture.md): share my saved videos with other devices — ON by default
+  p2pReceive: true,         // fetch from other devices when YouTube and the server can't — ON by default
   saveBeforePlay: false,    // download (server-muxed single file) before playing instead of streaming
   repeatMode: 'off',        // 'off' | 'all' — repeat the playing list when it ends
   loopOne: false,           // repeat the single current video
@@ -9874,6 +9876,10 @@ async function boot() {
   // Learn what's already cached, then top up any playlist videos that aren't.
   await refreshCachedIds();
   startCacheResyncWatch();
+  // Peer-to-peer: report what this device holds (on by default; settings.p2pShare).
+  if (WEB && window.P2PClient) {
+    window.P2PClient.start({ getSettings: () => data.settings, getProfile: () => (data.profile && data.profile.name) || '' });
+  }
   data.playlists.forEach(preloadPlaylist);
   preloadPinnedPlaylists();
   // Not awaited — artwork backfill must never delay first paint.