Releases semantically similar to an anchor release

Pulls the anchor's vector from the RELEASES_INDEX Vectorize index via getByIds, then runs a follow-up query with that vector. The anchor itself is always excluded from results. scope=org filters by the anchor's org id (Vectorize metadata filter on org_id); scope=global (default) is unscoped.

Degrades gracefully: when the binding is missing, the anchor isn't embedded yet, or Vectorize errors, the response is { degraded: true, degradedReason, items: [] } with HTTP 200 — callers render nothing in that case. degradedReason is human-readable and not stable.

Ranking: topK is over-fetched (min(max(limit * 10, 50), 100)), then candidates are ranked server-side by cosine × recency × contentWeight and sliced to limit. Content-free releases (empty bodies, boilerplate "no changes" notes) are dropped entirely; short-but-real releases are down-weighted; recency uses a 45-day half-life. Items are returned already in display order.