This PR adds support for specifying a color interpolation method for all
gradient utilities using a modifier:
```html
<div class="bg-linear-to-r/oklab">
```
Supported bare values are any valid color space keyword, as well as the
special keywords `shorter`, `longer`, `increasing`, and `decreasing`,
which are shortcuts for `in oklch {keyword} hue`.
Arbitrary values are also supported and are used as-is, so the `in`
keyword is not automatically included for you:
```html
<div class="bg-linear-to-r/[in_oklab]">
```
Modifiers are not supported when using arbitrary values for the actual
gradient, as it's expected that your arbitrary gradient value contain
all of the details you want in your gradient:
```html
<!-- Won't work -->
<div class="bg-linear-[to_right]/oklab">
<!-- Do this -->
<div class="bg-linear-[to_right_in_oklab]">
```
Resolves https://github.com/tailwindlabs/tailwindcss/issues/14955, but
it may still be wise to make `oklab` the default since I do sort of
agree with the poster there that most people probably expect a gradient
between two colors to sort of just "fade" between them rather than
interpolate between them around the color wheel.
---------
Co-authored-by: Adam Wathan <4323180+adamwathan@users.noreply.github.com>
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