- Add 4 new test cases to RealtimeHandlerRegistry test suite
- registerChannel stores outbound-only descriptors distinct from inbound
- listChannels() includes both inbound (from register) and outbound-only channels
- Validates backward-compat guarantee and re-registration behavior
Test count: 4 → 8 in realtime-handler-registry.test.ts
All 35 tests in core-realtime pass.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>