ADR-0087 exemption (no-migration-prescription): an enforcement-ORDER change plus one ADDITIVE optional key on a runtime context schema. No authorable key, spelling or stored shape moves, so a stored `sys_metadata` row needs no conversion and an upgrader has nothing to hand-edit. What changes is which image a `beforeUpdate` handler is shown; the remedy for a handler that depended on seeing a refused value is to read `ctx.submitted`, which is a code edit in the handler, not a metadata migration. Nothing is retired: `HookContext.submitted` is new and optional.