Pills with semi-transparent backgrounds were using raw color luminance to pick
text color, ignoring the page background showing through. This caused unreadable
text on dark themes for mid-luminance colors like orange. Now composites the
rgba background over the actual page bg (dark/light) before computing WCAG
contrast ratios, and centralizes the logic in a shared color-contrast utility.
Co-Authored-By: Paperclip <noreply@paperclip.ing>
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
