Add a second playback source and a weighted scheduler mixing it with
Navidrome:
- Scheduler picks a provider by SOURCE_WEIGHTS, falling through to the
others when one has nothing ready, so no source can stall playback.
- YtdlpProvider reads a hand-maintained config/urls.txt; container URLs
(playlist/album/label/artist) are flat-extracted and one entry is
drawn at random, honouring the anti-repeat window. Adds Track.source_url.
- YtdlpFetcher downloads bestaudio via the yt-dlp library, reusing the
atomic hidden-temp-then-rename pattern; Liquidsoap decodes the result.
- Queue now dispatches to a fetcher registry keyed by backend.
- Sweep orphaned download temp files on daemon startup (leftovers from a
killed container otherwise pile up and trip the stream fallback).
Verified end-to-end: yt-dlp opus decoded and served as 192 kbps MP3, and
the 3:1 default mix observed in play history.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Pierre-Olivier Mercier
d1db6a11d8