refactor nav coverage into clustered windows

Replace region-based runtime pathing with interest-cluster coverage windows so active nav areas stay contiguous and spawn anchors participate in initial coverage.

Assets/Scripts/VoxelWorld/VoxelWorldNavMeshLifetimeScope.cs

@@ -30,8 +30,9 @@ namespace VoxelWorldScene
 
             builder.RegisterMessagePipe();
             builder.RegisterInstance(config);
-            builder.RegisterInstance(worldGenerator).As<IChunkNavSourceReader>().As<IWorldInterestReader>().AsSelf();
-            builder.RegisterEntryPoint<VoxelWorldNavMeshService>();
+            builder.RegisterInstance(worldGenerator).As<IChunkNavSourceReader>().AsSelf();
+            builder.Register<SceneWorldInterestReader>(Lifetime.Singleton).As<IWorldInterestReader>();
+            builder.RegisterEntryPoint<VoxelWorldNavMeshService>().AsSelf();
             builder.RegisterBuildCallback(ResolvePublishers);
         }
 
@@ -48,4 +49,5 @@ namespace VoxelWorldScene
                 resolver.Resolve<IPublisher<WorldInterestChangedMessage>>());
         }
     }
+
 }