The backend code uses `@tldraw/state`, which is fine, but the package
has a peer dependency on `react`, which is not fine to impose on backend
consumers. So let's split this up again.
### Change type
- [ ] `bugfix`
- [ ] `improvement`
- [ ] `feature`
- [x] `api`
- [x] `other`
### Test plan
1. Create a shape...
2.
- [ ] Unit tests
- [ ] End to end tests
### Release notes
- Fixed a bug with…
