- upstream: _intros(mal_id) -> per-episode {start,length} (seconds),
30d TTL cache; Jikan is down or show uncovered -> [] (no button)
- app: GET /api/intros/{mal_id}, never errors into the player
- player: 'skip intro' pill appears while currentTime is inside the
intro window (+8s grace); click seeks past; reappears if rewound.
Ep-1 intros are often missing in MAL data, so falls back to the
show's first known timing (usually identical across eps)
- test: _parse_intros unit test (Jikan itself is 504ing right now,
live path verified by hand: endpoint returns [] cleanly)