feat: make the nearbyDistanceMeterClass a visitable class for GIZMO

Author: zepfred

core/src/main/java/ai/timefold/solver/core/config/solver/SolverConfig.java

@@ -704,6 +704,9 @@ public void visitReferencedClasses(Consumer<Class<?>> classVisitor) {
         if (scoreDirectorFactoryConfig != null) {
             scoreDirectorFactoryConfig.visitReferencedClasses(classVisitor);
         }
+        if (nearbyDistanceMeterClass != null) {
+            classVisitor.accept(nearbyDistanceMeterClass);
+        }
         if (terminationConfig != null) {
             terminationConfig.visitReferencedClasses(classVisitor);
         }

core/src/test/java/ai/timefold/solver/core/config/solver/SolverConfigTest.java

@@ -35,6 +35,7 @@
 import ai.timefold.solver.core.config.localsearch.LocalSearchPhaseConfig;
 import ai.timefold.solver.core.impl.heuristic.move.DummyMove;
 import ai.timefold.solver.core.impl.heuristic.selector.common.decorator.SelectionFilter;
+import ai.timefold.solver.core.impl.heuristic.selector.common.nearby.NearbyDistanceMeter;
 import ai.timefold.solver.core.impl.heuristic.selector.move.factory.MoveIteratorFactory;
 import ai.timefold.solver.core.impl.heuristic.selector.move.factory.MoveListFactory;
 import ai.timefold.solver.core.impl.heuristic.selector.move.generic.ChangeMove;
@@ -182,6 +183,7 @@ void visitReferencedClasses() {
         verify(classVisitor, atLeastOnce()).accept(DummyEasyScoreCalculator.class);
         verify(classVisitor, atLeastOnce()).accept(DummyConstraintProvider.class);
         verify(classVisitor, atLeastOnce()).accept(DummyIncrementalScoreCalculator.class);
+        verify(classVisitor, atLeastOnce()).accept(DummyNearbyDistanceClass.class);
         verify(classVisitor, atLeastOnce()).accept(DummyEntityFilter.class);
         verify(classVisitor, atLeastOnce()).accept(DummyValueFilter.class);
         verify(classVisitor, atLeastOnce()).accept(DummyChangeMoveFilter.class);
@@ -374,4 +376,12 @@ public abstract static class DummyMoveIteratorFactory implements MoveIteratorFac
     public abstract static class DummyMoveListFactory implements MoveListFactory<TestdataSolution> {
     }
 
+    public class DummyNearbyDistanceClass implements NearbyDistanceMeter<String, String> {
+
+        @Override
+        public double getNearbyDistance(String origin, String destination) {
+            return 0;
+        }
+    }
+
 }

core/src/test/resources/ai/timefold/solver/core/config/solver/testSolverConfigWithoutNamespace.xml

@@ -11,6 +11,7 @@
     <incrementalScoreCalculatorClass>ai.timefold.solver.core.config.solver.SolverConfigTest$DummyIncrementalScoreCalculator</incrementalScoreCalculatorClass>
     <initializingScoreTrend>ONLY_DOWN</initializingScoreTrend>
   </scoreDirectorFactory>
+  <nearbyDistanceMeterClass>ai.timefold.solver.core.config.solver.SolverConfigTest$DummyNearbyDistanceClass</nearbyDistanceMeterClass>
   <constructionHeuristic>
     <constructionHeuristicType>FIRST_FIT_DECREASING</constructionHeuristicType>
     <queuedEntityPlacer>