Fix api in lib folder.

frontend/src/lib/utils.ts

@@ -0,0 +1,46 @@
+import { clsx, type ClassValue } from 'clsx';
+
+export function cn(...inputs: ClassValue[]) {
+  return clsx(inputs);
+}
+
+export function formatCurrency(amount: number, currency: string = 'EUR'): string {
+  return new Intl.NumberFormat('en-US', {
+    style: 'currency',
+    currency: currency,
+  }).format(amount);
+}
+
+export function formatDate(date: string): string {
+  if (!date) return 'No date';
+
+  const parsedDate = new Date(date);
+  if (isNaN(parsedDate.getTime())) {
+    console.warn('Invalid date string:', date);
+    return 'Invalid date';
+  }
+
+  return new Intl.DateTimeFormat('en-US', {
+    year: 'numeric',
+    month: 'short',
+    day: 'numeric',
+  }).format(parsedDate);
+}
+
+export function formatDateTime(date: string): string {
+  if (!date) return 'No date';
+
+  const parsedDate = new Date(date);
+  if (isNaN(parsedDate.getTime())) {
+    console.warn('Invalid date string:', date);
+    return 'Invalid date';
+  }
+
+  return new Intl.DateTimeFormat('en-US', {
+    year: 'numeric',
+    month: 'short',
+    day: 'numeric',
+    hour: '2-digit',
+    minute: '2-digit',
+  }).format(parsedDate);
+}