BambuStudio

ENH/FIX: 3D view rotation and pan fixes and QoL improvements:

ENH: Added 3D view camera rotation mode with ALT modifier: Rotate around selection (if any) or cursor position.

CHANGE: Change/fix Brim Ears gizmo so that `SHIFT` key is required to be pressed for deselection, as well as `ALT`. This changes current behavior, but follows the convention of the rest of the GUI and allows for focused camera rotation using the `ALT` key when the gizmo is selected.