Live event stream (SSE)

Server-Sent Events stream of the job's live state. On connect the client receives the current snapshot (a status event, the latest progress, and the most recent preview if any), then future updates. The stream ends after the terminal status event.

Live push only — NOT a replayable log: events carry no id, there is no Last-Event-ID resume, and frames emitted while disconnected are gone. Each progress event is a complete snapshot, so a single one fully re-syncs a reconnecting client; the authoritative state is always GET /api/v2/jobs/{id}.