feat: Introduce onInputValueChange prop to SelectBox and MultiSelectBox components

[rebasedming]

Closes #444

What - This** PR exposes a new onInputValueChange prop to the SelectBox and MultiSelectBox components. As noted in the above issue, these components currently only have the onValueChange prop, which only fires when a menu item is selected. But, this prop does not fire when the user types into the search box, which prevents the developer from being able to capture user search input.

Why - Because of this missing prop, I was unable to use the SelectBox and MultiSelectBox in my application and had to create my own versions of these components as a workaround. In my application, there are tens of thousands of menu selection items, which cannot be loaded into the SelectBox all at once for performance reasons. I need to be able to listen to the user input so I can dynamically refresh the SelectBox menu options.

How - Mimicked the behavior of the onValueChange prop

[mitrotasios]

hi @rebasedming, thanks for the work! We are currently migrating all our input elements to headlessui for our v3 release coming by next week hopefully. Until then we would like to avoid pushing related changes. Happy to implement this from then on though :)

[rebasedming]

hi @rebasedming, thanks for the work! We are currently migrating all our input elements to headlessui for our v3 release coming by next week hopefully. Until then we would like to avoid pushing related changes. Happy to implement this from then on though :)

Oh, cool! I wasn't aware of a v3 release...is this going to deprecate v2 that just came out a few months ago?

[mitrotasios]

Yup, it will involve some breaking changes that will enable theming and we will be using headlessui under the hood for input components.

[severinlandolt]

Migrated to HeadlessUI in V3.