This PR cleans up some APIs around the editor's current page state:
- `setEditingShapeId` -> `setEditingShape`
- `setHoveredShapeId` -> `setHoveredShape`
- `setCroppingShapeId` -> `setCroppingShape`
- `setFocusedGroupId` -> `setFocusedGroup`
- `setErasingShapeIds` -> `setErasingShapes`
- `setHintingShapeIds` -> `setHintingShapes`
It also adds some additional computed getters, e.g.
`Editor.croppingShape`.
It also adds some errors around `setCroppingShape`.
### Change Type
- [x] `major` — Breaking change
### Test Plan
- [x] Unit Tests
13ef8be58d