feat: replace clsx with cn util

src/shared/ui/ControlGroup/ControlGroup.svelte

@@ -3,7 +3,7 @@
     Labeled container for form controls
 -->
 <script lang="ts">
-import clsx from 'clsx';
+import { cn } from '$shared/lib';
 import type { Snippet } from 'svelte';
 
 interface Props {
@@ -24,7 +24,7 @@ interface Props {
 const { label, children, class: className }: Props = $props();
 </script>
 
-<div class={clsx('flex flex-col gap-3 py-6 border-b border-subtle last:border-0', className)}>
+<div class={cn('flex flex-col gap-3 py-6 border-b border-subtle last:border-0', className)}>
     <div class="flex justify-between items-center text-xs font-primary font-bold tracking-tight text-neutral-900 dark:text-neutral-100 uppercase leading-none">
         {label}
     </div>