This PR prevents certain shapes from being edited while in readonly
mode. It adds `ShapeUtil.canEditInReadOnly` to allow developers to opt
in to editing shapes. It's currently applied only to embed shapes.
### Change Type
- [x] `major`
### Test Plan
1. In a readonly mode, try to edit text / sticky notes / arrow labels
via double click / enter. You should not be able to edit them.
2. Try to edit an embed. You should be able to edit it.
### Release Notes
- Prevent editing text shapes in readonly mode.
fb2f515b74