Add support for PHP 8.1 Backed Enums in Select, Checkboxes, Radio elements

@duadua do you have any narrative to add or is your MR pure experimentation?

I'd suggest creating a personal patch issue if its the latter, for example 📌 [ignore] @dpi's patch testing issue Active

@dpi
That's a great recommendation. I'll do that and experiment a bit more first, before posting a MR into this issue.

@dpi

To be honest I am confused whether to create MRs against 10.1.x or 11.x at this point.

Left some comments on the MR

We have some failing custom commands here (likely linting)

In 📌 Introduce and make use of NodePreview enum, to replace node related usage of DRUPAL_DISABLED, DRUPAL_OPTIONAL and DRUPAL_REQUIRED constants Active I'm looking to add a trait that allows you to do this very easily (although not quite like what is being proposed in the current MR).

The OptionsEnumTrait adds ::asOptions to an enum and forces a label method to be implemented. You can then use MyEnum::asOptions in the FAPI #options key, and also for things like field storage definitions with the allowed_values_function key