Public Get Review Queue

The team's review queue — the flag feed (TRA-935).

Same rows as the app's review page, reshaped for external consumers: created_by collapses to the source enum and internal PR links are dropped. Read-only; each row's trace_key feeds GET /v1/traces/{key}.

Resolves request_model here rather than inheriting it: the app's queue endpoint dropped that field to keep the review page's first paint off the per-row R2 body reads it costs. This is a published /v1 field, so the batch consumers who pay for it get it — the read is cached per key, and no interactive render waits on it.