feat(design): Fjord, a trial fifth scheme — Midnight's navy with a steel-blue accent and steel rules (E28)

frontend/src/design-lab/batchB.tsx

@@ -65,7 +65,7 @@ const pal = (
   accentFg: string,
 ): Pal => ({ bg, surface, border, fg, muted, accent, accentFg });
 
-// A literal copy of index.css's scheme tokens, so the four tiles render side by side (the live CSS
+// A literal copy of index.css's scheme tokens, so the tiles render side by side (the live CSS
 // switches only one scheme at a time). index.css is the source; theme.contract.test.ts holds it.
 const SCHEMES: SchemeDef[] = [
   {
@@ -88,6 +88,11 @@ const SCHEMES: SchemeDef[] = [
     dark: pal("#0b0e0b", "#111510", "#2a3226", "#d9ded6", "#8f9a8a", "#86a05a", "#0c1208"),
     light: pal("#f4f5f0", "#ffffff", "#dfe3d8", "#161a14", "#5a6352", "#556b2f", "#ffffff"),
   },
+  {
+    name: "Fjord · steel (trial)",
+    dark: pal("#0d1225", "#121931", "#25506e", "#eef1f5", "#9fb0c4", "#5aa1cb", "#0d1225"),
+    light: pal("#f3f6fa", "#ffffff", "#c9d6e3", "#152232", "#4f6278", "#256b8f", "#ffffff"),
+  },
 ];
 
 function Metric({ ok, children }: { ok: boolean; children: ReactNode }) {
@@ -461,7 +466,7 @@ export function BatchB() {
         id="b2"
         code="B2"
         title="The scheme set"
-        rule="Four schemes, four hue families: Midnight blue, Forest cyan, Slate fuchsia, Matrix moss. YouTube and Starship are gone (a user on them lands on Midnight). Rule: an accent is ≥ 30° of OKLCH hue from danger, warn and success, and ≥ 4.5:1 as text and under its button text, dark and light."
+        rule="Four schemes, four hue families: Midnight blue, Forest cyan, Slate fuchsia, Matrix moss. YouTube and Starship are gone (a user on them lands on Midnight). Fjord is a trial outside the rule (Midnight's family, Playnite's steel accent): folded into Midnight or removed. Rule: an accent is ≥ 30° of OKLCH hue from danger, warn and success, and ≥ 4.5:1 as text and under its button text, dark and light."
       >
         <div className="grid gap-2 grid-cols-[repeat(auto-fill,minmax(9.5rem,1fr))]">
           {SCHEMES.flatMap((s) =>