fix crash on mat creation after orm refactor

editor/editor_resource_picker.cpp

@@ -643,7 +643,7 @@ void EditorResourcePicker::drop_data_fw(const Point2 &p_point, const Variant &p_
 
 				if (at == "SpatialMaterial" && ClassDB::is_parent_class(dropped_resource->get_class(), "Texture")) {
 					// Use existing resource if possible and only replace its data.
-					Ref<Material3D> mat = edited_resource;
+					Ref<SpatialMaterial> mat = edited_resource;
 					if (mat.is_null()) {
 						mat.instance();
 					}

editor/plugins/spatial_editor_plugin.h

@@ -637,9 +637,8 @@ private:
 	RID indicators_instance;
 	RID cursor_mesh;
 	RID cursor_instance;
-	Ref<Material3D> indicator_mat;
+	Ref<SpatialMaterial> indicator_mat;
 	Ref<ShaderMaterial> grid_mat[3];
-	Ref<Material3D> cursor_material;
 
 	// Scene drag and drop support
 	Spatial *preview_node;