[Visual Refresh] Update docs to reflect new tokens

[mgadewoll]

Summary

Important

This PR merges into a feature branch.

Closes https://github.com/elastic/eui-private/issues/174

This PR updates the EUI and EUI+ docs to ensure the new and/or updated color tokens are reflected.

Changes

• adds output and docs for additional new tokens (text tokens, background tokens, border tokens)
• updates descriptions that mention computed color values, as Borealis is not generating colors anymore
• removes docs for color utilities that are deprecated (not expected to be promoted anymore)
• updates examples of color contrast to add additional color token options
• [fix]: updates brand color values for DARK mode - aligning it with design (I'm not sure why this was wrong, it might have been wrongly updated in a rebase 🫠)
• [cleanup]: updates (deprecated) token usages where new semantic tokens are available (e.g. dangerText -> textDanger or text -> textParagraph)

QA

• review the EUI and EUI+ docs
  • text tokens (EUI, EUI+)
  • background tokens (EUI, EUI+)
  • border tokens (EUI, EUI+)
  • color utilities (EUI, EUI+)
  • color contrast (EUI)
  • theme customization (EUI)

[tkajtoch]

The changes are looking solid! 🚢

[acstll]

Thank you @mgadewoll! I only have 2 non-blocking comments regarding text:

• the first paragraph in the Colors page has this statement (screenshot), I think it's no longer true, is it?
• the Shades and Special colors are deprecated in the current site but not the new
• extra: in the tokens table, I think it would be nice if the Sample for backgrounds and borders was not Aa but a "square" (this is maybe something for a new issue for EUI+?)

[mgadewoll]

Thank you @mgadewoll! I only have 2 non-blocking comments regarding text:

• the first paragraph in the Colors page has this statement (screenshot), I think it's no longer true, is it?
• the Shades and Special colors are deprecated in the current site but not the new
• extra: in the tokens table, I think it would be nice if the Sample for backgrounds and borders was not Aa but a "square" (this is maybe something for a new issue for EUI+?)

@acstll Thanks for the notes!

the first paragraph in the Colors page has this statement (screenshot), I think it's no longer true, is it?

True! I missed that one 🫠
I'll update to conditionally switch in current EUI docs, as the text is still correct for Amsterdam. But I think we can update EUI+ docs to use Borealis-only wording. Wdyt?
Updated in this commit.

the Shades and Special colors are deprecated in the current site but not the new

True! I missed updating the description as it's not actually using the JSDoc string anymore 🤦‍♀️ Thanks for the catch!
Updated in this commit.

extra: in the tokens table, I think it would be nice if the Sample for backgrounds and borders was not Aa but a "square" (this is maybe something for a new issue for EUI+?)

Ah yes, good call! 👍
Updated in this commit.

[kibanamachine]

Preview staging links for this PR:

• Docs site: https://eui.elastic.co/pr_8306/
• Storybook: https://eui.elastic.co/pr_8306/storybook
• New docs: https://eui.elastic.co/pr_8306/new-docs

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: 515464c

History

• 💚 Build #3400 succeeded 40e99ea

cc @mgadewoll

[acstll]

But I think we can update EUI+ docs to use Borealis-only wording. Wdyt?

👌