feat(themes): full revision of executive-slate — palette rebuild + real whole-swap bar

The executive-slate preset shipped a waybar.css that referenced @base/@accent
with no @define-color block, and no matching waybar.jsonc — so the raw-read
override ran a largely unstyled bar (the item-28 partial-whole-swap defect).
The palette was also flat (base->surface only 1.13x) with a dim accent
(#4D78CC, 3.91 on base).

- Palette: widen surface stepping (base->surface 1.13x -> 1.29x so panels/
  selection/hover separate), brighten the accent (#4D78CC -> #5A8AE6, 3.91 ->
  5.04 on base, now AA text), lift subtext/good/warn/bad a tier, realign ansi,
  soften bright-white (#FFFFFF -> #F0F3F9). text stays 12.5 AAA. Contrast
  checker: all 23 themes x 7 pairings pass.
- Waybar: complete the bespoke bar as a real whole-swap. New waybar.jsonc with
  the full 17-module set (parity with summer-day/night); waybar.css rewritten
  to lead with its own @define-color block and cover every module + state class
  the helper scripts emit (.recording/.activated/.on/.available/.dnd-*/battery).
  Identity: solid, edge-to-edge, sharp corners, accent underline on the active
  workspace.
- Rofi: drop the broken var() idiom for the house *{}/@name convention (split
  border syntax, message/textbox/scrollbar elements for the theme-grid picker).
- CONVENTIONS: Waybar parity rule now names executive-slate as a third
  whole-swap target (was stale at summer-only).

V1: nix flake check --no-build green; strict JSON parse of both files; real
rofi parsed the .rasi cleanly; with executive-slate set active, the module
eval resolves waybar.settings -> the jsonc, waybar.style -> the css, rofi.theme
-> the override rasi, and theme.nix accepts the palette. NOT yet done: on-screen
render of the bar/rofi/desktop (V2/V3) and preview.png (deferred to on-hardware
capture, per the chosen path).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

themes/executive-slate.json

@@ -5,39 +5,39 @@
   "mode": "dark",
   "wallpaper": "",
   "colors": {
-    "base": "#1A1D24",
-    "mantle": "#14161C",
-    "surface": "#232731",
-    "overlay": "#333947",
-    "text": "#D4DAE8",
-    "subtext": "#8792A6",
-    "muted": "#525A6E",
-    "accent": "#4D78CC",
-    "accentAlt": "#6C92D9",
-    "good": "#68A06B",
-    "warn": "#D19C4C",
-    "bad": "#C95F65"
+    "base": "#191C24",
+    "mantle": "#111319",
+    "surface": "#2A3040",
+    "overlay": "#3E4759",
+    "text": "#D7DDEA",
+    "subtext": "#9AA5BB",
+    "muted": "#5C6578",
+    "accent": "#5A8AE6",
+    "accentAlt": "#86A9F2",
+    "good": "#6FAE72",
+    "warn": "#DBA85A",
+    "bad": "#D06B71"
   },
   "border": {
     "active": "accent",
     "inactive": "overlay"
   },
   "ansi": [
-    "#232731",
-    "#C95F65",
-    "#68A06B",
-    "#D19C4C",
-    "#4D78CC",
-    "#836CC9",
-    "#4C99A0",
-    "#D4DAE8",
-    "#525A6E",
-    "#D67177",
-    "#7BB57F",
-    "#E0AF5E",
-    "#6C92D9",
-    "#9A84E0",
-    "#5FABB3",
-    "#FFFFFF"
+    "#2A3040",
+    "#D06B71",
+    "#6FAE72",
+    "#DBA85A",
+    "#5A8AE6",
+    "#8C79D6",
+    "#55A5AE",
+    "#D7DDEA",
+    "#5C6578",
+    "#DE7C82",
+    "#82BE85",
+    "#E7BB6E",
+    "#86A9F2",
+    "#A594E8",
+    "#6FBEC6",
+    "#F0F3F9"
   ]
 }