feat: German as the main language, English under /en, with a language switch

The site now exists in German (at the root, with /impressum and /datenschutz)
and English (/en). A request without a language follows the visitor's choice
from the language switch, then the browser language, then German; the old
English legal addresses move to /en for good.

All visible texts are data in src/content/de.ts and en.ts, so components hold
none of their own. The header carries a DE/EN switch whose bit curtain covers
the page while it is swapped and reopens at the same reading position. Title,
description, canonical, hreflang, Open Graph, the share image, the sitemap and
the structured data are per language. The privacy notice now describes the
cookie that remembers the chosen language.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/web/src/components/home/ClosingCta.tsx

@@ -3,16 +3,14 @@ import { Reveal } from "@/src/components/Reveal";
 import { EmailLink } from "@/src/components/EmailLink";
 import { BitAura } from "@/src/components/bits/BitAura";
 import { BitSeam } from "@/src/components/bits/BitSeam";
-import { BitHeadline, type BitLine } from "./BitHeadline";
+import type { Content } from "@/src/content/types";
+import { BitHeadline } from "./BitHeadline";
 import { ContactComposer } from "./ContactComposer";
 
-const CLOSING: readonly BitLine[] = [
-  { text: "LET'S", tone: "bits" },
-  { text: "TALK.", tone: "solid" },
-];
-
 /** ClosingCta: the contact section. One address and a message starter, no form to submit. */
-export const ClosingCta: React.FC = () => (
+export const ClosingCta: React.FC<{ contact: Content["contact"] }> = ({
+  contact,
+}) => (
   <section
     id="contact"
     data-glow
@@ -33,12 +31,11 @@ export const ClosingCta: React.FC = () => (
         <BitHeadline
           as="h2"
           invert
-          lines={CLOSING}
+          lines={contact.headline}
           className="font-sans text-[19vw] font-black leading-[0.86] tracking-tighter md:text-[13vw] lg:text-[8.5vw] xl:text-[9.5rem]"
         />
         <p className="m-0 mt-10 max-w-xl font-sans text-xl leading-snug text-slate-300 md:text-3xl">
-          Pick what you need and the email writes itself. Or write to me
-          directly:
+          {contact.lead}
         </p>
         <div className="mt-8">
           <EmailLink className="inline-block border-b-2 border-white pb-2 font-sans text-2xl font-bold tracking-tight text-white no-underline transition-opacity hover:opacity-70 md:text-4xl" />