Acknowledge ("Got it") changed operator instructions on this event

Every operator instruction that applies to one event, resolved server-side.

THE READ THE REVIEW PANEL MAKES. Resolving camera -> site -> account here rather than in the client is what keeps the instruction text OFF the queue bundle and off both SSE broadcasts: those payloads are built for every event an operator can see and are held open all shift, while this is one scoped fetch for the one event actually being reviewed. Same shape as the ai-eval and clip-url per-event reads, and guarded the same way.

THREE LEVELS, ALL THREE POSSIBLY EMPTY. account is null for a site that sits directly under the client with no account, and also for a site whose account has been retired — a retired account grants nothing and its text must not be served. site and camera are always present for a real event.

DEMO EVENTS ANSWER 404 (Round-0 ruling Q7), not a null camera: they are camera-less by construction and the review panel never shows one, so a fourth shape would be dead code the client still had to handle.

Out-of-scope and unknown event ids are indistinguishable — both 404 — so this route is not an event-id oracle.