B2B-88: add starter kit structure and elements

packages/ui/src/lib/utils/cn.ts

@@ -0,0 +1,7 @@
+import { clsx } from 'clsx';
+import type { ClassValue } from 'clsx';
+import { twMerge } from 'tailwind-merge';
+
+export function cn(...inputs: ClassValue[]) {
+  return twMerge(clsx(inputs));
+}