i18n: paraglide setup mirroring played/plaza, de unprefixed + /en/ prefixed

- project.inlang/settings.json with locales [de, en], baseLocale de.
- messages/{de,en}.json hold the strings (tagline, blog labels, etc.).
- vite.config.ts: paraglideVitePlugin compiles to src/paraglide/
  (gitignored) on dev/build. Strategy: url → cookie →
  preferredLanguage → baseLocale. URL pattern keeps German at /:path
  (unprefixed) and English at /en/:path so existing URLs stay valid.
- server.tsx wraps the handler in paraglideMiddleware so AsyncLocalStorage
  carries the per-request locale into SSR.
- router.tsx adds rewrite { input: deLocalizeUrl, output: localizeUrl }
  so route matching stays locale-agnostic — the router sees /blog while
  URLs show /en/blog.
- cms.ts narrows getLocale()'s union back to the de|en pair the CMS
  supports, used as the default for find/findGlobal calls.
- Components/routes switch to m.foo() for user-visible strings; date
  formatting picks de-DE / en-GB from getLocale().
- Root html lang reads getLocale() so the document language flips per
  request.

Known minor: TanStack Start's { title } meta entry still serves the base
locale value (og:title and the description meta are localized correctly).
Will track separately.

vite.config.ts

@@ -1,3 +1,4 @@
+import { paraglideVitePlugin } from "@inlang/paraglide-js";
 import tailwindcss from "@tailwindcss/vite";
 import { tanstackStart } from "@tanstack/react-start/plugin/vite";
 import viteReact from "@vitejs/plugin-react";
@@ -10,11 +11,26 @@ export default defineConfig({
 		dedupe: ["react", "react-dom"],
 	},
 	plugins: [
+		paraglideVitePlugin({
+			project: "./project.inlang",
+			outdir: "./src/paraglide",
+			// Prefer the URL prefix (so /en/* loads English), fall back to a
+			// persisted cookie, then the browser language, then the base locale (de).
+			strategy: ["url", "cookie", "preferredLanguage", "baseLocale"],
+			// German lives at /:path (unprefixed), English under /en/:path.
+			urlPatterns: [
+				{
+					pattern: "/:path(.*)?",
+					localized: [
+						["en", "/en/:path(.*)?"],
+						["de", "/:path(.*)?"],
+					],
+				},
+			],
+		}),
 		tailwindcss(),
 		tanstackStart(),
-		nitro({
-			preset: "bun",
-		}),
+		nitro({ preset: "bun" }),
 		viteReact(),
 	],
 });