fix: build and test stability for design overhaul

Fixed missing types, import errors, and updated test suites to match the new editorial design. Verified Docker container build.

app/[locale]/layout.tsx

@@ -3,7 +3,6 @@ import { setRequestLocale } from "next-intl/server";
 import React from "react";
 import { notFound } from "next/navigation";
 import ConsentBanner from "../components/ConsentBanner";
-import { getLocalizedMessage } from "@/lib/i18n-loader";
 
 // Supported locales - must match middleware.ts
 const SUPPORTED_LOCALES = ["en", "de"] as const;