Add colordx

[dkryaklin]

Adds colordx to Color.

Checklist:

• I've read and understood Contributing Guidelines.
• I've added the new resource at the end of its section.
• This resource is out there for a while, and actively maintained.
• This resource is popular enough and has at least a few hundred stars on GitHub. — ~120 stars, but ~4M weekly npm downloads and a runtime dependency of cssnano, UnoCSS and the Evil Martians OKLCH picker.

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colordx is a zero-dependency, immutable color library built for CSS Color 4: OKLCH, OKLab, Display-P3 and Rec.2020 alongside hex, rgb and hsl, with a colord-style chainable API plus gamut mapping, WCAG contrast and CIEDE2000. It is the fastest library in this section on the project's benchmark suite against chroma-js, culori, color, tinycolor2 and colord. MIT, TypeScript, documented at https://colordx.dev.

[gokaygurcan]

Please follow the PR template.