fix(i18n): update consent banner on locale switch

Use next-intl translations instead of reading NEXT_LOCALE cookie once, so banner text updates immediately when switching languages.

fix(activity-feed): make loading UI match dark theme

Avoid the white loading card on hard reload by using the same dark styling as the normal feed.

Co-authored-by: dennis <dennis@konkol.net>

app/components/ConsentBanner.tsx

@@ -1,49 +1,28 @@
 "use client";
 
-import React, { useMemo, useState } from "react";
+import React, { useState } from "react";
 import { useConsent, type ConsentState } from "./ConsentProvider";
+import { useTranslations } from "next-intl";
 
 export default function ConsentBanner() {
   const { consent, setConsent } = useConsent();
   const [draft, setDraft] = useState<ConsentState>({ analytics: false, chat: false });
   const [minimized, setMinimized] = useState(false);
-
-  const locale = useMemo(() => {
-    if (typeof document === "undefined") return "en";
-    const match = document.cookie
-      .split(";")
-      .map((c) => c.trim())
-      .find((c) => c.startsWith("NEXT_LOCALE="));
-    if (!match) return "en";
-    return decodeURIComponent(match.split("=").slice(1).join("=")) || "en";
-  }, []);
+  const t = useTranslations("consent");
 
   const shouldShow = consent === null;
   if (!shouldShow) return null;
 
-  const s = locale === "de"
-    ? {
-        title: "Datenschutz-Einstellungen",
-        description:
-          "Wir nutzen optionale Dienste (Analytics und Chat), um die Seite zu verbessern. Du kannst deine Auswahl jederzeit ändern.",
-        essential: "Essentiell",
-        analytics: "Analytics",
-        chat: "Chatbot",
-        acceptAll: "Alles akzeptieren",
-        acceptSelected: "Auswahl akzeptieren",
-        rejectAll: "Alles ablehnen",
-      }
-    : {
-        title: "Privacy settings",
-        description:
-          "We use optional services (analytics and chat) to improve the site. You can change your choice anytime.",
-        essential: "Essential",
-        analytics: "Analytics",
-        chat: "Chatbot",
-        acceptAll: "Accept all",
-        acceptSelected: "Accept selected",
-        rejectAll: "Reject all",
-      };
+  const s = {
+    title: t("title"),
+    description: t("description"),
+    essential: t("essential"),
+    analytics: t("analytics"),
+    chat: t("chat"),
+    acceptAll: t("acceptAll"),
+    acceptSelected: t("acceptSelected"),
+    rejectAll: t("rejectAll"),
+  };
 
   if (minimized) {
     return (