-- Adds a nullable `notes` column to research_publish_approvals so a
-- reviewer rejecting a publish can include revision guidance the next
-- coordinator run picks up (R2 — reject-with-revision loop).
--
-- The notes are stashed on the approval row, then `start_topic` reads the
-- most recent rejected approval for the topic and prepends its notes to
-- the coordinator task string as "Prior review notes:". This closes the
-- loop without duplicating the run-spawn code — the reviewer's critique
-- steers the next iteration through the same start_topic path.
--
-- NULL means "reject with no revision guidance" — legacy behavior stays
-- correct (topic stays in reviewing, nothing else fires).
ALTER TABLE research_publish_approvals
    ADD COLUMN notes TEXT;