fix(theme): generated waybar/rofi CSS invisible on on-surface palettes (item 27)

Follow-on to the swaync fix (a643391): the generated Waybar CSS colored
the module row and #window @subtext and dim states @muted, and the
generated rofi theme put @fg text on @surface chips — invisible where
palettes use those roles as "on-surface" (flexoki-light: subtext==base,
surface==text; gruvbox: muted/base = 1.27). flexoki-light has no
whole-swap, so it ran this CSS. Generated surfaces only — the summer
whole-swaps are hand-authored and untouched.

- waybar: secondary text → alpha(@text, 0.85); dim states (inactive
  workspaces, DND bell, muted volume) → alpha(@text, 0.5).
- rofi: @dim → text+"80", @surface → text+"1a" (#RRGGBBAA fg tints).
- check-theme-contrast.py pairings/docs now cover all three generated
  surfaces; status glyphs (good/warn/bad on base, worst 2.05) are
  deliberately not held to a text ratio — raising them is palette
  design, a human decision.

Verified: V0; V1 (checks.theme-contrast green over 21 themes;
downstream-template-home builds; rendered waybar style has zero
@subtext/@muted/@surface; rendered custom.rasi shows fg-derived
tints). Honesty: NOT visually verified — V3 queued (flexoki-light
eyeball + dark-theme regression spot-check).

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

agent/BACKLOG.md

@@ -25,26 +25,6 @@ next, in what order*.
 *Items 21–27: real-hardware QA findings from the Latitude 5410
 (Bernardo, 2026-07-04) — bugs found on metal outrank the queue.*
 
-### 27. Generated waybar/rofi CSS invisible on on-surface palettes
-Found by item 25's audit: the generated Waybar CSS colors `#window` and
-the whole module row `@subtext`, and the generated rofi theme puts `@fg`
-text on `@surface` backgrounds (inputbar, textbox, `element alternate`).
-In palettes where subtext/surface mean "on-surface" (flexoki-light:
-subtext==base AND surface==text) those are invisible. summer-day/night
-escape via their whole-swap waybar.css/rofi.rasi — **flexoki-light does
-not** and runs the generated CSS. Same class of fix as the shipped
-swaync one (63136a8-follow-on): move the generated surfaces to pairings
-that contrast by construction (alpha(@text) tints; @text for module
-text with per-module accents kept), then extend
-tools/check-theme-contrast.py's PAIRINGS to cover waybar/rofi so
-`checks.theme-contrast` guards them too. Waybar changes must respect
-the parity rule (generated bar only — the summer whole-swaps are
-hand-authored and unaffected). Alternative worth weighing in-iteration:
-normalize the flexoki-light palette itself (make subtext dim-text,
-surface elevated-bg) — smaller diff but changes the theme's look
-everywhere. **Verify:** V1 + the extended contrast check across all 21
-themes; V2 themed-VM screenshot on flexoki-light if cheap; V3 eyeball.
-
 ### 22. Network menu shows nameless/weird entries
 Reported: `networkmanager_dmenu` lists entries with no names (likely
 hidden-SSID APs rendered as blank rows, possibly other adapters/