Completeness/duration verification was applied only to the first candidate that
downloaded successfully; if that copy was incomplete or too short the whole job
failed, even when a later-ranked source had a complete copy (e.g. John Mayer 'The
Search for Everything' — Qobuz reliably fails one hi-res track, so it never fell
back to the deluxe edition or Soulseek).
Extract the checks into a pure _download_problem() and run it INSIDE the download
loop: a candidate that downloads but fails verification now falls through to the
next-ranked source, and the job only fails (needs_attention) when every candidate
is incomplete — reporting the last shortfall reason.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Jonathan