feat: dynamically load mermaid.js

src/lib/components/chat/Chat.svelte

@@ -1,7 +1,6 @@
 <script lang="ts">
 	import { v4 as uuidv4 } from 'uuid';
 	import { toast } from 'svelte-sonner';
-	import mermaid from 'mermaid';
 	import { PaneGroup, Pane, PaneResizer } from 'paneforge';
 
 	import { getContext, onDestroy, onMount, tick } from 'svelte';