fix(youtube): prevent playlist URLs from stalling yt-dlp probes (#180)

src/core/services/youtube/ytdlp-command.ts

@@ -4,6 +4,13 @@ import path from 'node:path';
 const DEFAULT_YTDLP_COMMAND = 'yt-dlp';
 const WINDOWS_YTDLP_COMMANDS = ['yt-dlp.cmd', 'yt-dlp.exe', 'yt-dlp'];
 
+/**
+ * yt-dlp expands `list=`/`index=` URL params into the whole playlist unless told not to, which
+ * makes single-video extraction hang (e.g. a full Watch Later list) until our timeouts fire.
+ * Every yt-dlp invocation targeting one video must include this.
+ */
+export const YTDLP_SINGLE_VIDEO_ARG = '--no-playlist';
+
 function resolveFromPath(commandName: string): string | null {
   if (!process.env.PATH) {
     return null;