1af10d0f4a
- Messages now carry senderName (resolved actorId → sourceHandle.externalId) so clients render usernames instead of raw actor cuids. - GET /v1/dev/users exposes the dev directory (DEV_USERS keys) so a host app can validate add-by-username; real apps validate against their user store / MDM. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>