Make undo work as expected

[WestonThayer]

It often takes more than one undo for only a single Blok layout to actually be undone. This can be fixed on the native side, there's a way to set operations to undo-silent. We'd need to do all Transforms on art on the native side though, and that means we need a way to "pass" an object from JS to C++. That would be super hard. Workaround is to just undo a few more times.