feat(web): management console — TanStack Start + orval + shadcn + Paraglide

Browser UI for the host's management REST API (mgmt.rs / docs/api/openapi.json).

Stack, exactly as specified:
- TanStack Start (Vite, SPA mode) — file-based routes, SSR shell + client hydration.
- React Query via orval codegen from the checked-in OpenAPI spec: a custom fetch mutator
  (src/api/fetcher.ts) centralizes the base URL, the bearer token (Settings → localStorage),
  JSON, and a throwing ApiError; the query client skips retries on 4xx. orval returns the
  response body directly (includeHttpResponseReturnType:false) so a query's `.data` is the
  typed payload; GET→useQuery, POST/DELETE→useMutation by method.
- shadcn/ui on Tailwind v4 (CSS-first tokens, dark-first) — button/card/badge/input/label/
  table/skeleton primitives hand-authored from the canonical source.
- Paraglide i18n (en + de) with a reactive useLocale() hook and a language switcher.

Pages: dashboard (live status — video/audio/session/stream, stop-session + request-IDR,
2s polling), host (identity/codecs/ports), clients (paired list + unpair), pairing (PIN
submit, polls pin_pending), settings (API token + language).

Dev server proxies /api → 127.0.0.1:47990 (same-origin, no CORS; PUNKTFUNK_MGMT_URL to
override). Generated code (orval client, paraglide runtime, routeTree) is gitignored and
reproduced by `pnpm codegen` (prepare/pre* scripts). Validated live against `serve`: API
shapes match, dev proxy works, SSR shell renders the localized nav, build + tsc green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

web/src/components/app-shell.tsx

@@ -0,0 +1,74 @@
+import type { ReactNode } from 'react'
+import { Link } from '@tanstack/react-router'
+import { Activity, Server, Users, KeyRound, Settings, Radio } from 'lucide-react'
+import { m } from '@/paraglide/messages'
+import { useLocale, changeLocale, locales, type Locale } from '@/lib/i18n'
+import { cn } from '@/lib/utils'
+
+const NAV = [
+  { to: '/', icon: Activity, label: () => m.nav_dashboard() },
+  { to: '/host', icon: Server, label: () => m.nav_host() },
+  { to: '/clients', icon: Users, label: () => m.nav_clients() },
+  { to: '/pairing', icon: KeyRound, label: () => m.nav_pairing() },
+  { to: '/settings', icon: Settings, label: () => m.nav_settings() },
+] as const
+
+export function AppShell({ children }: { children: ReactNode }) {
+  // Read the locale so the whole shell re-renders on a language switch.
+  useLocale()
+  return (
+    <div className="flex min-h-screen">
+      <aside className="hidden w-60 shrink-0 flex-col border-r bg-card/40 p-4 sm:flex">
+        <div className="mb-6 flex items-center gap-2 px-2">
+          <Radio className="size-5 text-[var(--success)]" />
+          <div>
+            <div className="font-semibold leading-tight">{m.app_name()}</div>
+            <div className="text-xs text-muted-foreground">{m.app_tagline()}</div>
+          </div>
+        </div>
+        <nav className="flex flex-col gap-1">
+          {NAV.map(({ to, icon: Icon, label }) => (
+            <Link
+              key={to}
+              to={to}
+              activeOptions={{ exact: to === '/' }}
+              className="flex items-center gap-3 rounded-md px-3 py-2 text-sm text-muted-foreground transition-colors hover:bg-accent hover:text-foreground"
+              activeProps={{ className: 'bg-accent text-foreground font-medium' }}
+            >
+              <Icon className="size-4" />
+              {label()}
+            </Link>
+          ))}
+        </nav>
+        <div className="mt-auto pt-4">
+          <LanguageSwitcher />
+        </div>
+      </aside>
+      <main className="flex-1 overflow-x-hidden">
+        <div className="mx-auto max-w-5xl p-6 sm:p-10">{children}</div>
+      </main>
+    </div>
+  )
+}
+
+function LanguageSwitcher() {
+  const current = useLocale()
+  return (
+    <div className="flex gap-1" role="group" aria-label="Language">
+      {locales.map((l: Locale) => (
+        <button
+          key={l}
+          onClick={() => changeLocale(l)}
+          className={cn(
+            'rounded px-2 py-1 text-xs uppercase transition-colors',
+            l === current
+              ? 'bg-secondary text-secondary-foreground font-medium'
+              : 'text-muted-foreground hover:text-foreground',
+          )}
+        >
+          {l}
+        </button>
+      ))}
+    </div>
+  )
+}