`ED_GIZMO_CAGE2D_STYLE_CIRCLE` now draw circles. The previous `ED_GIZMO_CAGE2D_STYLE_CIRCLE`, which drew rectangles, is renamed to `ED_GIZMO_CAGE2D_STYLE_RECTANGLE`. The meaning of `ED_GIZMO_CAGE2D_STYLE_BOX` is now unclear and probably needs to be renamed too.
Ref T104280
Maniphest Tasks: T104280
Differential Revision: https://developer.blender.org/D17174