Add types to Card (#2730)

Author: Alex-Tideman

src/lib/holocene/card.svelte

@@ -1,5 +1,11 @@
 <script lang="ts">
-  let { class: className = '', children } = $props();
+  import type { Snippet } from 'svelte';
+
+  type Props = {
+    class?: string;
+    children?: Snippet;
+  };
+  let { class: className = '', children }: Props = $props();
 </script>
 
 <div class="surface-primary border border-subtle p-4 {className}">