feat: replace clsx with cn util

src/shared/ui/FooterLink/FooterLink.svelte

@@ -3,8 +3,8 @@
     Standard footer link with arrow icon and hover effects.
 -->
 <script lang="ts">
+import { cn } from '$shared/lib';
 import ArrowUpRightIcon from '@lucide/svelte/icons/arrow-up-right';
-import clsx from 'clsx';
 import type { HTMLAnchorAttributes } from 'svelte/elements';
 
 interface Props extends HTMLAnchorAttributes {
@@ -32,7 +32,7 @@ let {
 
 <a
     {href}
-    class={clsx(
+    class={cn(
         'group inline-flex items-center gap-1 text-2xs font-mono uppercase tracking-wider-mono',
         'text-neutral-400 hover:text-brand transition-colors',
         'bg-surface/80 dark:bg-dark-bg/80 backdrop-blur-sm px-2 py-1 pointer-events-auto',