feat(#119): accept route states in heartbeat and state-change events

Replace ACK-based route state inference with agent-reported state.
Heartbeats now carry optional routeStates map, and ROUTE_STATE_CHANGED
events update the registry immediately.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

cameleer3-server-core/src/main/java/com/cameleer3/server/core/agent/RouteStateRegistry.java

@@ -6,7 +6,8 @@ import java.util.concurrent.ConcurrentHashMap;
 
 /**
  * In-memory registry tracking the operational state of routes.
- * State is inferred from successful route-control command ACKs.
+ * State is updated from agent heartbeats (routeStates map) and
+ * ROUTE_STATE_CHANGED lifecycle events.
  * On server restart, all states reset to STARTED (default Camel behavior).
  */
 public class RouteStateRegistry {