chore: import upstream snapshot with attribution

apps/docs/lib/utils.ts

@@ -0,0 +1,26 @@
+import { type ClassValue, clsx } from 'clsx'
+import { twMerge } from 'tailwind-merge'
+
+/**
+ * Combines multiple class names into a single string, merging Tailwind classes properly
+ */
+export function cn(...inputs: ClassValue[]) {
+  return twMerge(clsx(inputs))
+}
+
+/**
+ * Get the full URL for an asset stored in Vercel Blob
+ * - If CDN is configured (NEXT_PUBLIC_BLOB_BASE_URL), uses CDN URL
+ * - Otherwise falls back to local static assets served from root path
+ */
+export function getAssetUrl(filename: string) {
+  // Absolute URLs (e.g. blob-hosted academy videos) are already complete.
+  if (/^https?:\/\//.test(filename)) {
+    return filename
+  }
+  const cdnBaseUrl = process.env.NEXT_PUBLIC_BLOB_BASE_URL
+  if (cdnBaseUrl) {
+    return `${cdnBaseUrl}/${filename}`
+  }
+  return `/${filename}`
+}