A big playlist read '97' because yt-dlp flat caps playlist extraction at ~100 and
its playlist_count is often unset, so we showed the FETCHED count. Now the detail
endpoint overlays the InnerTube playlist browse (browseId VL<id>): curator-ordered
videos up to ~200 (vs yt-dlp's ~100) AND the real count from the header's
numVideosText (e.g. '512 videos'). The billboard shows the true total; when the
list is partial it says 'Showing the first N of TOTAL videos (YouTube limits
playlist browsing).' Live-validated (Veritasium uploads: total 512, 200 loaded).
103 tests green.
Honest cap: YouTube's browse only exposes ~200 of a playlist (page 2 returns no
continuation), so very large playlists show the right COUNT but list ~200.
8e56273c9d