add geant4 scene and gcompose app

app/gcompose/CMakeLists.txt

@@ -0,0 +1,20 @@
+
+add_executable(gcompose src/main.cpp)
+
+target_include_directories(gcompose PRIVATE 
+    ${SRC_DIR}
+    ${PROJECT_BINARY_DIR}
+    ${Geant4_INCLUDE_DIRS}
+    ${VTK_INCLUDE_DIRS}
+)
+
+target_link_libraries(gcompose
+    mutomCore
+    mutomMath
+    mutomGeant
+    mutomVtk
+    ${Geant4_LIBRARIES}
+    ${VTK_LIBRARIES}
+)
+
+install(TARGETS gcompose RUNTIME DESTINATION bin)

app/gcompose/src/main.cpp

@@ -0,0 +1,45 @@
+
+#include "Math/ContainerBox.h"
+#include <HEP/Geant/Scene.h>
+
+#include <Vtk/uLibVtkViewer.h>
+#include <Vtk/vtkContainerBox.h>
+
+#include <vtkSmartPointer.h>
+#include <vtkCubeSource.h>
+#include <vtkPolyDataMapper.h>
+#include <vtkActor.h>
+#include <vtkRenderer.h>
+
+#include <iostream>
+
+using namespace uLib;
+
+int main(int argc, char** argv) {
+    std::cout << "Starting gcompose application..." << std::endl;
+
+    uLib::ContainerBox world_box(Vector3f(100, 100, 100));
+
+    uLib::Scene scene;
+    scene.ConstructWorldBox(&world_box, "G4_AIR");
+    scene.Initialize();
+
+    // 2. Initialize VTK Viewer
+    Vtk::Viewer viewer;
+
+    uLib::Vtk::vtkContainerBox vtk_box(&world_box);
+    viewer.AddPuppet(vtk_box);
+
+    viewer.GetRenderer()->Render();
+
+    std::cout << "Geant4 and VTK scenes are ready." << std::endl;
+    std::cout << "Starting VTK Interactor..." << std::endl;
+
+    // 3. Start VTK interactor (blocks until window is closed)
+    viewer.Start();
+
+    // 4. Clean up
+    std::cout << "Shutting down..." << std::endl;
+
+    return 0;
+}