-- Full answer content for one trace row (answer text, blocks, citations,
-- quick replies, plan, candidate assessments, disclaimer) — everything a
-- client needs to redraw the assistant turn without re-running the query.
-- Nullable/additive: existing rows simply have no replayable answer, and
-- `/v1/rag/transcript` degrades to showing just the user turn for those.
ALTER TABLE rag_retrieval_trace
    ADD COLUMN IF NOT EXISTS response_payload jsonb;