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/imprint-body.tsx

@@ -0,0 +1,57 @@
+"use client"
+
+import { ObfuscatedEmail } from "@/components/obfuscated-email"
+import { ObfuscatedAddress } from "@/components/obfuscated-address"
+
+interface ImprintBodyProps {
+  html: string
+}
+
+/**
+ * Renders imprint HTML with {email} and {address} placeholders replaced by
+ * ObfuscatedEmail and ObfuscatedAddress components.
+ */
+export function ImprintBody({ html }: ImprintBodyProps) {
+  const placeholderRegex = /\{(email|address)\}/g
+  const parts: (string | React.ReactNode)[] = []
+  let lastIndex = 0
+  let match
+  let key = 0
+
+  while ((match = placeholderRegex.exec(html)) !== null) {
+    const before = html.slice(lastIndex, match.index)
+    if (before) {
+      parts.push(
+        <span
+          key={`html-${key++}`}
+          style={{ display: "contents" }}
+          dangerouslySetInnerHTML={{ __html: before }}
+        />
+      )
+    }
+    if (match[1] === "email") {
+      parts.push(
+        <ObfuscatedEmail
+          key={`email-${key++}`}
+          className="text-emerald-600 outline-none transition-colors hover:text-emerald-500 focus-visible:ring-2 focus-visible:ring-emerald-500 focus-visible:ring-offset-2"
+        />
+      )
+    } else {
+      parts.push(<ObfuscatedAddress key={`addr-${key++}`} />)
+    }
+    lastIndex = match.index + match[0].length
+  }
+
+  const after = html.slice(lastIndex)
+  if (after) {
+    parts.push(
+      <span
+        key={`html-${key++}`}
+        style={{ display: "contents" }}
+        dangerouslySetInnerHTML={{ __html: after }}
+      />
+    )
+  }
+
+  return <>{parts}</>
+}