turn the terminal/Gruvbox theme into the skeuo console

- rename the theme everywhere: id terminal -> skeuo, desktop sim skeuo -> desktop,
  skeleton terminal shell -> SkeuoLayout, page.css -> shared.css (shared components),
  old skeuo.css -> desktop.css, storage key theme -> dmx-theme (with migration)
- rebuild the theme as a walnut-and-aluminium home-lab console: brass plates, patch bay,
  analogue gym gauges, clipboard, stitched leather logbook, service rack with pilot lamps,
  framed print, chart recorder, cartridge, software box, pegboard tags, card-index drawer
- all materials are CSS + inline-SVG noise (no texture images); Barlow Semi Condensed +
  Courier Prime via next/font with fallbacks
- desktop mode is now phone-only (<=768px): switch hidden above that, stored desktop
  preference overridden, sim never mounted on wide viewports
- drop the ASCII train background and its gruvbox.webp asset

src/app/layout.tsx

@@ -1,8 +1,28 @@
 import type { Metadata } from "next";
-// Removed unused google fonts since we use local Custom Mono
+import { Barlow_Semi_Condensed, Courier_Prime } from "next/font/google";
 import "./globals.css";
 import ThemeScript from "./components/ThemeScript";
 
+// The skeuo theme's two voices: an engraved-panel grotesque for metal
+// (labels, headings, controls) and a typewriter for anything on paper.
+// Both get an explicit fallback stack so the page still reads correctly
+// if the webfont never arrives.
+const panel = Barlow_Semi_Condensed({
+  variable: "--font-panel",
+  subsets: ["latin"],
+  weight: ["500", "600", "700"],
+  display: "swap",
+  fallback: ["Arial Narrow", "Helvetica Neue", "Arial", "sans-serif"],
+});
+
+const typewriter = Courier_Prime({
+  variable: "--font-typewriter",
+  subsets: ["latin"],
+  weight: ["400", "700"],
+  display: "swap",
+  fallback: ["Courier New", "Courier", "monospace"],
+});
+
 export const metadata: Metadata = {
   title: "dvorakmortonxd.dev",
   description: "Martin Dvořák's personal website.",
@@ -25,7 +45,12 @@ export default function RootLayout({
   children: React.ReactNode;
 }>) {
   return (
-    <html lang="en" data-theme="skeuo" suppressHydrationWarning>
+    <html
+      lang="en"
+      data-theme="skeuo"
+      suppressHydrationWarning
+      className={`${panel.variable} ${typewriter.variable}`}
+    >
       <body className="antialiased">
         <ThemeScript />
         {children}