-- v1.1 (contract request 5): an assistant message's citations live in its own column.
-- v1 stored them as an extra row with role 'sources' right after the assistant row (ids sort in write order).
-- Fold each such row into the assistant row before it, then drop every 'sources' row.
ALTER TABLE ai_messages ADD COLUMN citations_json TEXT;
UPDATE ai_messages SET citations_json = (
  SELECT s.content FROM ai_messages s
  WHERE s.conversation_id = ai_messages.conversation_id AND s.role = 'sources'
    AND s.id = (SELECT MIN(n.id) FROM ai_messages n WHERE n.conversation_id = ai_messages.conversation_id AND n.id > ai_messages.id)
) WHERE role = 'assistant';
DELETE FROM ai_messages WHERE role = 'sources';