-- 0009_chat_session_pinned down: drop the pinned ordering column added by the up
-- migration. SQLite DROP COLUMN (3.35+) is already relied on by 0006/0007, and the
-- column is not referenced by any index, so a plain drop is safe and lossless (the
-- pin is order metadata, not data the session needs to remain valid).

ALTER TABLE chat_sessions DROP COLUMN pinned;