Add Drupal headless stack with Next.js frontend

- Add Next.js frontend service (nextjs) with Dockerfile and source
- Update docker-compose.yml: image names, Drupal 11.3.3, nextjs service
- Add docker-compose.override.yml.disabled for dev hot-reload
- Add install-headless-modules.sh for OAuth/JSON:API module setup
- Add README.md with full setup and configuration guide
- Update nginx/Dockerfile and nginx.conf.template for cms. subdomain
- Update drupal/Dockerfile PHP-FPM build args
- Gitignore **/.vscode/ to prevent IDE workspace files from being tracked

drupal/nextjs/components/obfuscated-address.tsx

@@ -0,0 +1,49 @@
+"use client"
+
+import { useEffect, useState } from "react"
+
+/**
+ * Renders a mailto link only after client mount so the email is not in the
+ * server-rendered HTML, reducing harvestability by bots that scan static HTML.
+ * Parts are hardcoded so they live in the JS bundle, not in page HTML.
+ */
+type AddressData = {
+  fullname: string
+  street: string
+  city: string
+  country: string
+}
+
+export function ObfuscatedAddress({ className }: { className?: string }) {
+  const [address, setAddress] = useState<AddressData | null>(null)
+
+  useEffect(() => {
+    setAddress({
+      fullname: "Robert Nasarek",
+      street: "Kleine Ulrichstraße 1",
+      city: "Halle (Saale)",
+      country: "Germany",
+    })
+  }, [])
+
+  if (!address) {
+    return (
+      <span className={className}>
+        <noscript>Robert Nasarek, Kleine Ulrichstraße 1, Halle (Saale), Germany</noscript>
+        <span aria-hidden>…</span>
+      </span>
+    )
+  }
+
+  return (
+    <p className={className}>
+      {address.fullname}
+      <br />
+      {address.street}
+      <br />
+      {address.city}
+      <br />
+      {address.country}
+    </p>
+  )
+}