Cross-process against the real arr binary, real ffmpeg and real alass:
a provider fetch synced and named under DESIGN.md §15, never
re-searched once satisfied; an embedded English track extracted and
translated into a .mt sidecar; an implausible sync kept unsynced and
surfaced in the missing-subtitles queue. Podnapisi and the translation
backend are stubbed at the HTTP/process boundary, never a live tracker
or a live translation API.