feat: Security CSRF Fix, Logout optimierung, Footer Anpassung, Rechtstexteanpassung

src/app/api/newsletter/route.ts

@@ -7,9 +7,15 @@ import { sendMail } from "@/lib/mail";
 import { newsletterConfirmEmail } from "@/lib/email-templates";
 import { getBaseUrl } from "@/lib/url";
 import { verifyTurnstileToken } from "@/lib/turnstile";
+import { isTrustedOrigin } from "@/lib/csrf";
 import { getLocale } from "@/i18n/locale";
 
 export async function POST(request: Request) {
+  // Route-Handler haben keinen eingebauten CSRF-Schutz — siehe lib/csrf.ts.
+  if (!isTrustedOrigin(request)) {
+    return NextResponse.json({ error: "Ungültige Anfrage." }, { status: 403 });
+  }
+
   const ip = await getClientIp();
   if (!rateLimit(`newsletter:${ip}`, 5, 60 * 60 * 1000)) {
     return NextResponse.json(