Disambiguate class name vs object name; rename InterferenceFunction -> Interference

• Remove the dynamic setting of names.
• Resolve the long-standing ambiguity of class name vs object name.
• INode now has a virtual function className; final children also have static member class_name.
• To resolve an inconsistency between GUI and core, rename InterferenceFunction -> Interference.
• Provide MultiLayer::setSampleName, yet unsupported in the GUI.

GUI/Models/GUIDomainSampleVisitor.cpp

@@ -82,7 +82,7 @@ SessionItem* GUIDomainSampleVisitor::populateSampleModel(SampleModel* sampleMode
 
     m_topSampleName = sample_name;
     if (m_topSampleName.isEmpty())
-        m_topSampleName = sample.className().c_str();
+        m_topSampleName = sample.sampleName().c_str();
 
     for (const auto& [child, depth, parent] : NodeUtils::progenyPlus(&sample)) {
         setDepth(depth + 1);
@@ -129,7 +129,7 @@ void GUIDomainSampleVisitor::visit(const Layer* sample)
 void GUIDomainSampleVisitor::visit(const MultiLayer* sample)
 {
     auto multilayer_item = m_sampleModel->insertItem<MultiLayerItem>();
-    multilayer_item->setItemName(sample->className().c_str());
+    multilayer_item->setItemName(sample->sampleName().c_str());
     multilayer_item->setCrossCorrLength(sample->crossCorrLength());
     multilayer_item->setExternalField(sample->externalField());
     m_levelToParentItem[depth()] = multilayer_item;