The streaming-fallback seek recovery loop + its visual coverup move
into `src/store/seekFallbackState.ts`:
- 6 module mutables (retry timer + start + target; fallback trackId +
restartAt; visual target)
- 3 const gates (180 ms retry interval, 6 s retry budget, 1.6 s
visual guard)
- `scheduleSeekFallbackRetry(trackId, seconds)` — bounded retry loop
that hits `audio_seek` every 180 ms up to 6 s, re-scheduling on
recoverable errors and clearing the visual target on success or
hard failure
- `clearSeekFallbackRetry()` — cancel timer + reset state
- get/set accessors for the three caller-touched fields
(`SeekFallbackVisualTarget`, trackId, restartAt)
playerStore's ~30 direct-access sites become accessor calls. Inside
the progress handler the visual target is captured into a local once
per call so type narrowing + repeated reads stay clean.
17 focused tests pin the constants, get/set round-trips, the retry
loop's happy path (setSeekTarget + clear visual), recoverable retry
re-schedule, non-recoverable abort, track-change abort, retry-budget
exhaustion, and the three coalesce cases (different track id /
seconds delta > 0.25 s / seconds delta ≤ 0.25 s).
playerStore 2909 → 2869 LOC.
Frank Stellmacher
0eb084c5f8