make scene able to run parallel simulations

src/HEP/Geant/Scene.h

@@ -60,6 +60,9 @@ public:
 
   /// Initialize the Geant4 run manager with detector, physics, and action.
   void Initialize();
+  
+  /// Set the verbosity level for console output (default 0)
+  void SetVerbosity(int level);
 
   /// Run the simulation for nEvents muons.
   /// Results are appended to the provided vector.