message: add default transform to user-added textures
diff: #include "sg/visitors/GenerateImGuiWidgets.h" // TreeState
  #include "rkcommon/os/FileName.h"
  +#include "rkcommon/math/AffineSpace.h"
  #include <string>
  #include <vector>
  #include <imgui.h>
  +using namespace rkcommon::math;
  +
  void AdvancedMaterialEditor::buildUI(NodePtr materialRegistry)
  {
  static int currentMaterial = -1;
  @@ -105,6 +108,7 @@ void AdvancedMaterialEditor::buildUI(NodePtr materialRegistry)
  sgTex->load(matTexFileName, true, false);
  auto newMat = copyMaterial(selectedMat, "", paramStr);
  newMat->add(sgTex, paramStr);
  + newMat->createChild(paramStr + ".transform", "linear2f") = linear2f(one);
  materialRegistry->add(newMat);
  }
  }
  