Deep-review round 3 of bug hunt 2026-09.
- `failed` is now final only for a track that can never be text (bitmap, no item/track/file). A Plex
hiccup or a stretch ffmpeg could not read answers `unavailable`: said, polled again every 5 s, and
the <track> stays mounted when cues exist elsewhere (gen > 0). Re-picking the selected track asks
the server again at once.
- Within LOOKAHEAD_S of a covered stretch's end the next window is read ahead, instead of only once
the playhead has fallen off it (subtitles dropped out at every edge while the full pass was backed
off or slower than a window lasts).
- Windows and full passes run on separate pools with separate in-flight caps, so a window never
queues behind (or is refused by) minute-long full passes — the pool comment promised that and
nothing enforced it.
- A pass that times out is TERMinated and keeps what it reached (published as partial) instead of
being killed and discarded.
- Lapsed failure memos are swept on every write (they were only pruned when the same key was read
again, so polling fresh keys grew the process without bound).
- `publish` no longer merges into a sidecar with no VTT behind it, or claims a region whose VTT write
failed, or overwrites an unreadable track with one window.
- A NUL in a rating_key names no row (it was a DataError, a 500, on every Plex route) and no longer
500s the status poll.
Tests: 16 new, each mutation-checked (18 mutations, all red on the test that names them).
peter
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