Fix gizmo doesn't coerce to a supported operation when selection changes

[adamkewley]

• If I select something in the editor that is rotate-able
• And then I click the "rotation" button, to show the rotation gizmo
• Then it shows the rotation gizmo
• But if I then select something that is only move-able (e.g. a Station)
• Then it shows no gizmo (Stations cannot be moved)
• But it should show a translation gizmo