- redownload: never clobber a co-held (deduped) asset. Drop the force-reset-to-pending;
_release_asset already deletes+recreates a solo asset (genuine re-fetch), while a shared
ready asset is left intact and the re-queued job re-points to it via _finish_from_cache —
so one user's re-download can't delete another's file mid-serve (finding #1).
- redownload: reset queue_pos to the tail so a re-download doesn't front-run newer queued
jobs on the worker's `ORDER BY queue_pos` claim (finding #3). Made service.next_queue_pos public.
- formats: video-only mp4 selector prefers every video-only option before any progressive
`best`, so a "Video only" download stays audio-free whenever a video-only stream exists (#2).
- titles: a title that is only the engagement prefix no longer resurrects the stripped stats
(return the stripped text / empty, not the raw) (#4).
- worker: probe the file's duration when yt-dlp gave none, so a long re-encode shows real
progress instead of a frozen 0% (#5); tighten the ensure_browser_playable docstring to its
actual mp4-profile scope (#6).
peter
cae5702fbb