Replace modifying primitive meshes with scaling of the mesh instance

source/arviz_godot/lib/avi/scene/Converter.cpp

source/arviz_godot/lib/avi/scene/CubeElementNode.cpp

source/arviz_godot/lib/avi/scene/CubeElementNode.h

source/arviz_godot/lib/avi/scene/CylinderElementNode.cpp

source/arviz_godot/lib/avi/scene/CylinderElementNode.h

source/arviz_godot/lib/avi/scene/CylindroidElementNode.cpp

source/arviz_godot/lib/avi/scene/CylindroidElementNode.h

source/arviz_godot/lib/avi/scene/EllipsoidElementNode.cpp

source/arviz_godot/lib/avi/scene/EllipsoidElementNode.h

source/arviz_godot/lib/avi/scene/MeshElementNode.cpp

source/arviz_godot/lib/avi/scene/MeshElementNode.h

source/arviz_godot/lib/avi/scene/SphereElementNode.cpp

source/arviz_godot/lib/avi/scene/SphereElementNode.h