Duotone using theme/Style colors does not update when theme/Style colors are changed

[jordesign]

Description

What I expect

When a duotone filter is using the theme's preset colors (eg. Contrast/Primary/Secondary set from Global Styles) I expect the duotone to update when I make changes to the color presets.

What happens

Instead when changing the preset colors - the duotone filter retains the old colors and shows them as hex values instead of the preset name.

Step-by-step reproduction instructions

1. Set up an image/cover block with the Duotone Filter. For the highlight and shadow values - select preset colors.
2. Change the preset colors in Site Editor > Styles > Colors
3. Return to the image/cover block and see that the duotone filter has not updated.

Screenshots, screen recording, code snippet

duotone-color-palette.mov

Environment info

• WP6.2 & GB15.4
• TwentyTwentyThree

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes

[jordesign]

For additional context it seems that is related to the Duotone values being stores as hex instead of CSS variables.
Related issue here - but specifically related to Style variations:
#46547

And more related to the Social Icons block:
#35480
#36462

There's also an existing PR for switching to CSS Custom properties for Duotone
#42870

[jordesign]

more additional context....

I ran into this issue when trying to create a Block Pattern for submission. The use case being that it would be great to have a pattern be inserted and have the Duotone automatically reference the user's preset colors when inserted.

[annezazu]

@MaggieCabrera and @ajlende curious what you all think here!

[MaggieCabrera]

Yeah, I believe it's because are saved as hex, when that gets solved we should check that this issue gets resolved as well