ADR-0087 exemption (no-migration-prescription): no metadata body, authorable key or stored shape moves: the driver table keeps `memory`, `mingo`, `in-memory` and `inmemory` on its config-contract face, so `resolveDriverId` answers them exactly as before and a stored `datasource.driver: memory` still parses against `MemoryConfigSchema`; what narrows is the boot selection (`--database-driver`, `OS_DATABASE_DRIVER`, `databaseDriver`, a `memory://` or `mingo://` database URL, and a project's default datasource declared on the engine), which is host configuration that `objectstack migrate meta` does not rewrite — and no rewrite would be truthful, since the only replacement is a different engine the operator has to choose. The other categories are closed on facts: all three packages publish (not `unpublished`); no ADR-0087 id covers a boot selection (not `registered` / `already-registered`); and the change is runtime behaviour plus exported constant values, not an interface or a type alone (not `runtime-interface-only` / `type-surface-only`).