CREATE TABLE plan_revisions (
 id uuid PRIMARY KEY DEFAULT gen_random_uuid(),
 user_id uuid NOT NULL REFERENCES users(id) ON DELETE CASCADE,
 plan_id uuid NOT NULL REFERENCES roast_plans(id) ON DELETE CASCADE,
 plan jsonb NOT NULL,
 name text NOT NULL DEFAULT '',
 created_at timestamptz NOT NULL DEFAULT now()
);
CREATE INDEX plan_revisions_plan ON plan_revisions(user_id, plan_id, created_at DESC);
ALTER TABLE actual_roasts ADD COLUMN IF NOT EXISTS manual_key text;
CREATE UNIQUE INDEX actual_roasts_manual_once ON actual_roasts(user_id, manual_key);
ALTER TABLE actual_roasts ADD COLUMN IF NOT EXISTS plan_snapshot jsonb;