delivery.VersionNumbered with VersionNumberedEvent and VersionNumberedSubject is the body the builder says when it
numbers a version, so a build module consumes it from mesh-sdk instead of the builder's internal package.
BuildAnswer gains out-of-step, so the builder decodes a trunk build's compare by its field, not by name.
Claude-Session: https://claude.ai/code/session_01JG73KJNrH5EgFXMKKYSrig
