ADR-0087 exemption (no-migration-prescription): nothing is retired, renamed or added: no authorable key changes, no stored shape is rewritten, and `objectstack migrate meta` has nothing to reach. Every rule id, severity and fix-it text crossed here is unchanged — only the surface each runs on widens, from the three CLI commands to the runtime publish door as well. An affected tenant corrects its own metadata against a message the rule already shipped, which is tenant data rather than a spec migration.