-- v1.1 (contract request 4): per-course mentor toggles get their own table. A row exists only while the learner
-- has switched the course's mentor rules off. v1 kept them in ai_settings.config_json.mentorOff; reading that JSON
-- is not portable SQL, so upgradeAiData (src/upgrade.ts) copies it on first start.
CREATE TABLE ai_mentor_prefs (
  user_id TEXT NOT NULL, course_id TEXT NOT NULL, off INTEGER NOT NULL, updated_at TEXT NOT NULL,
  PRIMARY KEY (user_id, course_id)
);