This ensures all imported types are using the `type` keyword.

Will be used in the new and existing components.

Right now Next.js does barrel file optimization and re-writing imports
to a real path in the `dist` folder. Most of those rewrites don't
actually exist because they have an assumption:

```js
import { FooBar } from '@headlessui/react'
```

is rewritten as:
```js
import { FooBar } from '@headlessui/react/dist/components/foo-bar/foo-bar'
```

This script will make sure these paths exist...

This hook has a default implementation when comparing objects. If the
object contains an `id`, then we will compare the objects by their
`id`'s without the user of the library needing to specify `by="id"`.

If the objects don't have an `id` prop, then the default is still to
compare by reference (unless specicified otherwise).

…ed components

…(singular)

This is so that we can be consistent with the other components.

This is a more complex version of a soon to be exported `mergeProps`
that we will be using in our components.

These are the ones being exposed inside `data-headlessui-state="..."`

These playgrounds are mainly test playgrounds. Lower priority for now,
we will get back to them.