extract and sort the colors, and reduce their number

[severo]

The styles are nearly the same, but it will be easier to customize.

Screencast.From.2025-09-23.18-38-37.mp4

[Copilot]

Pull Request Overview

This PR refactors the CSS custom properties (CSS variables) for colors in the HighTable component by introducing a systematic naming convention and consolidating the color palette. The changes replace the old scattered color definitions with a more organized system using "hy-" prefixed variables, reducing the total number of color variables while maintaining the same visual appearance.

• Introduced systematic color naming with --hy-color-*, --hy-accent-*, and --hy-highlight-* prefixes
• Consolidated color definitions from scattered variables into organized color groups
• Updated all color references to use the new systematic naming convention

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[severo]

asking for a review @platypii, because it might slightly break customized styles if they used --light-border-color (low possibility that it affects any user at all). I think we can increment the minor number, just in case.

[platypii]

Nice simplification