bug: buttons with low contrast, aria-disabled support, buttons in filter

[pdanpdan]

Reproduction URL (Required)

https://play.tailwindcss.com/xdk5JEP7oO

What version of daisyUI are you using?

latest

Which browsers are you seeing the problem on?

All browsers

Describe your issue

follow up from #4413

I have prepared 3 playgrounds that should cover most of the normal usage:

• 5.4.7: https://play.tailwindcss.com/uUitizu33y?layout=preview
• 5.4.8+: https://play.tailwindcss.com/mkA67TyHx8?layout=preview
• proposed: https://play.tailwindcss.com/GfY2pUJqSu
• proposed:
  • https://play.tailwindcss.com/fFMOnwp7wJ?layout=preview (with override border color for outlined/dash)
  • https://play.tailwindcss.com/ALlb5S0ygS?layout=preview (with border in color of button)
• full rewrite: https://play.tailwindcss.com/FRkdjEChM3?layout=preview
• full rewrite: https://play.tailwindcss.com/QZaRC8aifn?layout=preview (reordered styles, adjusted layers, cleanup comments - for initial commented variant see above)

Problems:

• if buttons (checkbox) are used in .filter they do not show active status
  addressed in feat(filter): show all options on keyboard navigation #4427

• aria-disabled="true" is not accounted for
  adressed in proposal by adding it to disabled states

• on all dark themes .btn-neutral .btn-soft cannot be used
  addressed in proposal by introducing a variable to set the soft bg color for neutral (--btn-soft-bg: var(--color-neutral-content) 80%;)

• .btn-soft, .btn-outline, .btn-dash, .btn-ghost, .btn-link when there is contrast between fg (--btn-fg) and bg (--btn-color) button color, but there is no contrast in rest state between bg (derivative of --color-base-100 or page bg) and fg (--btn-color)
  addressed in proposal by introducing a user facing variable --btn-rest-fg that sets the fg color for buttons in rest state (only for soft, outline, dash, ghost) - it is ignored for .btn-neutral because that color has its own rules
  .btn-link does not need any mitigation because it uses the same color all the time, so it can already be set by the user
  in the example --btn-rest-fg is set for the whole theme, but it can be used for individual buttons also

• a checkable button cannot be identified as checked/unchecked when focused
  addressed in full rewrite

• setting --btn-color and ``--btn-fg` on buttons does not work as expected
  addressed in full rewrite

[github-actions]

Thank you @pdanpdan for reporting issues. It helps daisyUI a lot 💚
I'll be working on issues one by one. I will help with this one as soon as a I find a solution.
In the meantime providing more details and reproduction links would be helpful.