CREATE TABLE assessor_artifact_deletion_outbox (
  id text PRIMARY KEY CHECK (btrim(id) <> ''),
  project_id text NOT NULL CHECK (btrim(project_id) <> ''),
  artifact_id text NOT NULL CHECK (btrim(artifact_id) <> ''),
  storage_key text NOT NULL UNIQUE CHECK (btrim(storage_key) <> ''),
  attempts integer NOT NULL DEFAULT 0 CHECK (attempts >= 0),
  next_attempt_at timestamptz NOT NULL,
  created_at timestamptz NOT NULL,
  last_error_code text,
  data jsonb NOT NULL CHECK (jsonb_typeof(data) = 'object')
);

CREATE INDEX assessor_artifact_deletion_outbox_due_idx
  ON assessor_artifact_deletion_outbox(next_attempt_at, created_at, id);