Cleanup: Improve comment about CurvesGeometry::resize()

Make it clearer that attributes must be initialized by the caller.

Pull Request: https://projects.blender.org/blender/blender/pulls/114004

source/blender/blenkernel/BKE_curves.hh

@@ -344,8 +344,10 @@ class CurvesGeometry : public ::CurvesGeometry {
 
  public:
   /**
-   * Change the number of elements. New values for existing attributes should be properly
-   * initialized afterwards.
+   * Change the number of curves and/or points.
+   *
+   * \warning To avoid redundant writes, newly created attribute values are not initialized.
+   * They must be initialized by the caller afterwards.
    */
   void resize(int points_num, int curves_num);