-- events 도메인 PR-1 (4/11) — event_actor enum
-- 어떤 actor/process 가 row 를 만들었는가 (created_by + events_history.changed_by 공용)
-- source 와 분리: source=email + created_by=email_ingest 같은 직교 축

CREATE TYPE event_actor AS ENUM (
    'manual',
    'eid',
    'email_ingest',
    'system'
);