Fix runtime default locale resolution

lib/toast.tsx

@@ -6,7 +6,7 @@ import {
   type ToastPosition,
 } from "react-hot-toast";
 
-import { resolveLocale } from "@/lib/locale";
+import { FALLBACK_LOCALE, resolveLocale } from "@/lib/locale";
 
 type ToastVariant = "default" | "success" | "error" | "loading";
 
@@ -14,13 +14,13 @@ type ToastMessage = string;
 
 function getCurrentLocale() {
   if (typeof window === "undefined") {
-    return "de" as const;
+    return FALLBACK_LOCALE;
   }
 
   const pathname = window.location.pathname;
-  const maybeLocale = pathname.split("/")[1] || "de";
+  const maybeLocale = pathname.split("/")[1] || FALLBACK_LOCALE;
 
-  return resolveLocale(maybeLocale);
+  return resolveLocale(maybeLocale, FALLBACK_LOCALE);
 }
 
 function getToastPosition(isArabic: boolean): ToastPosition {