Defines two backward-compatible mechanisms for accurate route state
tracking: heartbeat extension (routeStates map in heartbeat body)
and ROUTE_STATE_CHANGED events for real-time updates. Covers
agent-side detection via Camel EventNotifier, server-side handling,
multi-agent conflict resolution, and migration path.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
