- Entrypoint: for legacy DBs, add is_admin via raw SQL then stamp head
(instead of running full migration chain which fails on existing tables)
- Fixed admin_api_keys.py Pydantic config (dict → ConfigDict)
- Added tests/test_alembic_migrations.py (PostgreSQL-only integration tests)
- Fixed infinite recursion in _create_table_if_not_exists (QA catch)
