feat: implement Geant Material class, add object registration, and update PropertyWidget signal handling and read-only state

src/HEP/Geant/Matter.cpp

@@ -0,0 +1,21 @@
+
+#include "HEP/Geant/Matter.h"
+#include <Geant4/G4Material.hh>
+#include <Geant4/G4NistManager.hh>
+
+using namespace uLib::Geant;
+
+Material::Material() : m_G4Data(nullptr) {}
+
+Material::Material(const char *name) : m_G4Data(nullptr) {
+    this->SetFromNist(name);
+}
+
+Material::~Material() {
+    if(m_G4Data) delete m_G4Data;
+}
+
+void Material::SetFromNist(const char *name) {
+    G4NistManager* man = G4NistManager::Instance();
+    m_G4Data = man->FindOrBuildMaterial(name);
+}