fix(web): all accent text and icons use accent-fg (#5318)

The raw accent fails AA as text on every dark surface, not only on its
own tint: 3.04:1 on the page, 2.70 on iron, 2.21 on slate, against 4.5.
accent-fg (the house formula, 45% toward parchment) measures 5.62 at
worst across both modes. The operator chose the readable colour over the
signature teal for text, on 2026-10-08.

- 36 sites swap. They are 35 Tailwind uses: links, "Now playing", the
  ingest progress line, active shuffle/repeat, the liked heart, the app
  download icon and its hover. The last is the alphabet rail's pending
  spinner in CSS. Icons follow the text: as graphics they need only
  3:1, and the raw accent misses even that on iron.
- check-tint-contrast adds accent to TEXT_NEVER_RAW, so a new raw
  text-accent or color: var(--fs-accent) fails the web lane. Run against
  the files before the swap, it finds all 36. Borders, rings and fills
  keep the raw accent.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/tailwind.config.js

@@ -26,8 +26,10 @@ export default {
         accent: {
           DEFAULT: 'var(--fs-accent)',
           tint: 'color-mix(in srgb, var(--fs-accent) 12%, transparent)',
-          // Accent TEXT on an accent tint (#3150). The raw accent on its own
-          // tint measures 1.97:1 at worst; this measures 5.03.
+          // All accent TEXT and icons use this, on a tint or not (#3150,
+          // #5318). The raw accent measures 1.97:1 on its own tint and 2.21 on
+          // slate at worst; this measures 5.03 and 5.62. The raw accent stays
+          // for borders, rings and fills, where it is a graphic, not text.
           fg: 'var(--fs-accent-fg)'
         },
         warning: { DEFAULT: 'var(--fs-warning)', fg: 'var(--fs-warning-fg)' },