This PR is just a chore to prepare for future performance optimizations.
Essentially I want to improve the performance of the `Menu`, `Listbox`
and `Combobox` components but I want to do it in separate PRs such that
reverting the improvements can be done if needed.
This PR just sets up a `Machine` for state machines, and adds some
helpers such as a `useSlice` to calculate parts of the state machine.
Component using the `useSlice` will only re-render _if_ the slice
changes.
So apart from adding a library (`useSyncExternalStoreWithSelector`) and
adding some setup code. Nothing in this PR changes the behavior of the
components.
Robin Malfait
e2a63760aa