youtube-music-dl test video — album with an UNSTRUCTURED tracklist.

This lists per-track DURATIONS (not cumulative timestamps) and does not start
with 0:00, so YouTube will NOT auto-generate chapters. yt-dlp sees zero chapters.
This is the case an agent handles by parsing the tracklist, accumulating the
durations into start/end times, and passing the result as a --chapters-file.

Tracklist:
1. Alpha [0:12]
2. Bravo [0:12]
3. Charlie [0:12]
