This PR improves the "back to content" behavior. Rather than using an
interval, we now add a "camera-stopped" event that triggers the check.
### Change Type
- [x] `sdk` — Changes the tldraw SDK
- [x] `improvement`
### Test Plan
1. Create some shapes, then move the camera to an empty part of the
canvas.
2. Check that the back to content button appears.
3. Ensure that the back to content button does not appear when the
canvas is empty.
We use `children: any` in a bunch of places, but the proper type for
these is `ReactNode`. This diff fixes those.
### Change Type
- [x] `patch` — Bug fix
Rename `@tldraw/tldraw` to just `tldraw`! `@tldraw/tldraw` still exists
as an alias to `tldraw` for folks who are still using that.
### Test Plan
- [x] Unit Tests
- [ ] End to end tests
### Release Notes
- The `@tldraw/tldraw` package has been renamed to `tldraw`. You can
keep using the old version if you want though!
This PR fixes a check on whether the dot com multiplayer editor has been
loaded in an iframe.
It tries to keep it working on tldraw.com itself.
### Change Type
- [x] `patch` — Bug fix
### Test Plan
1. Load me in an iframe
Steve Ruiz