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/lib/i18n.ts

@@ -0,0 +1,29 @@
+// Thin reactive layer over Paraglide. Paraglide's `m.*` message functions and
+// `setLocale`/`getLocale` are framework-agnostic; this hook re-renders React when the
+// locale changes (Paraglide's localStorage strategy persists the choice across reloads).
+import { useSyncExternalStore } from 'react'
+import { getLocale, setLocale, locales } from '@/paraglide/runtime'
+
+/** The available locales as a union (`'en' | 'de'`), derived from Paraglide's `locales`. */
+export type Locale = (typeof locales)[number]
+
+const listeners = new Set<() => void>()
+
+/** Switch locale and notify subscribers (Paraglide also persists it per its strategy). */
+export function changeLocale(locale: Locale) {
+  // `reload: false` keeps the SPA mounted; we re-render via the store below.
+  setLocale(locale, { reload: false })
+  for (const l of listeners) l()
+}
+
+function subscribe(cb: () => void) {
+  listeners.add(cb)
+  return () => listeners.delete(cb)
+}
+
+/** Current locale, reactive — components using `m.*` should read this so they re-render. */
+export function useLocale(): Locale {
+  return useSyncExternalStore(subscribe, getLocale, () => 'en' as Locale)
+}
+
+export { locales }

web/src/lib/utils.ts

@@ -0,0 +1,7 @@
+import { clsx, type ClassValue } from 'clsx'
+import { twMerge } from 'tailwind-merge'
+
+/** shadcn/ui's class combiner: merge conditional classes, dedupe Tailwind conflicts. */
+export function cn(...inputs: ClassValue[]) {
+  return twMerge(clsx(inputs))
+}