fix(themes): P1 palette retunes from the design audit + gated subtext floor (item 28b)

The audit's P1s, fixed at the palette level (items 25/27 previously
patched the consumers around these):
- summer-day: surface was the TEXT color (slate #5c6a72 on cream) and
  subtext was the BASE (ratio 1.0, invisible) — now a raised cream
  surface #efe7d0 and a slate-teal subtext #6e828a in the theme's
  family.
- flexoki-light: surface/overlay/muted were all the text black and
  subtext the paper — retuned to canonical upstream Flexoki tones
  (ui #E6E4D9, #B7B5AC, tx-2 #6F6E69, base-500 #878580).
- miasma: pure-black surface under a #222 base → raised #2e2e2e.
- kanagawa: surface was sumiInk0 (darker than the bg) → upstream's
  raised sumiInk4 #2a2a37.
check-theme-contrast.py gains the adopted rule: subtext on base >= 3.0
(all 21 themes pass), so the invisible-secondary-text class cannot
ship again. Model note in the backlog: `overlay` is a mid-tone role
(catppuccin semantics), not a third bg tier.

Verified: V0 + checks.theme-contrast green (21x3); re-audit shows all
four P1 findings gone; a scratch downstream with summer-day active
builds and the new surface hex lands in the rendered ghostty config.
Remains: V3 four-theme eyeball (HARDWARE-QUEUE) and 28b's P2 floors +
exemption list.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

agent/HARDWARE-QUEUE.md

@@ -153,6 +153,13 @@ QA machine), the **T14s** (webcam case).
       applies the matching profile within ~3s (toast names it);
       unplugging switches back; Auto-switch off stops that; with two
       profiles naming the same outputs, no flapping (ties do nothing).
+- [ ] **Retuned palettes eyeball (item 28b P1)** — switch through
+      summer-day, flexoki-light, kanagawa, miasma: chips/menus/toasts
+      now draw on a *raised* surface (summer-day's was slate-on-cream,
+      kanagawa's near-black, miasma's pure black), secondary text
+      (tooltips, fastfetch labels) is visible on summer-day +
+      flexoki-light, kanagawa floats are lighter than the bg (upstream
+      sumiInk4). Anything that reads worse than before → reopen 28b.
 - [ ] **Themed greeter + console (item 16)** — after `sys-rebuild` +
       logout: tuigreet renders in theme colors (dark container, accent
       border, themed prompt/time) and a raw tty (CTRL+ALT+F2) shows the