refactor: rename Puppet class to Prop3D across the codebase

src/Math/Assembly.h

@@ -41,7 +41,7 @@ namespace uLib {
  * transformation that is applied on top of each child's own transform.
  *
  * A bounding box is automatically computed from all contained objects and
- * can be queried or shown/hidden through the VTK puppet.
+ * can be queried or shown/hidden through the VTK prop3d.
  */
 class Assembly : public ObjectsContext, public TRS {
 public:
@@ -81,7 +81,7 @@ public:
 
     /**
      * @brief Controls whether the bounding box wireframe should be shown
-     * in the viewer (used by the VTK puppet).
+     * in the viewer (used by the VTK prop3d).
      */
     void SetShowBoundingBox(bool show);
     bool GetShowBoundingBox() const;