PROTOCOL.md §20.10: hello's integrations.zLevels, and nothing more
(D374). PLAN_REDESIGNS §14.3.20 records the build, two points settled in
code, the tests and the rig check; pointers from §9's summary and
§14.3.6.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY