fix(client): avoid crypto.randomUUID() TypeError by adding uuid helper

Add a small, robust UUID helper and replace direct uses of crypto.randomUUID()
in the client to avoid a runtime TypeError in browsers/environments that do not
implement crypto.randomUUID which caused the frontend to crash and show the
"Browser not supported / JavaScript changes.

Author: Matthias Kastner

client/src/lib/components/Toggle.svelte

@@ -3,10 +3,11 @@
     label: string;
     checked?: boolean;
   }
+  import { uuid } from '$lib/uuid';
 
   let { label, checked = $bindable(), class: extraClass = '', ...rest }: Props = $props();
 
-  const id = `toggle-${crypto.randomUUID()}`;
+  const id = `toggle-${uuid()}`;
 </script>
 
 <div class="flex items-center gap-2 {extraClass}">

client/src/lib/utils.ts

@@ -1,3 +1,5 @@
+import { uuid } from './uuid';
+
 declare const umami: {
   track: (event_name: string, data?: Record<string, any>) => void;
   identify: (unique_id: string) => void;
@@ -11,7 +13,7 @@ export function initializeAnalytics(): void {
     const umamiIdKey = 'mvw_uuid';
     let uniqueId = localStorage.getItem(umamiIdKey);
     if (!uniqueId) {
-      uniqueId = crypto.randomUUID();
+      uniqueId = uuid();
       localStorage.setItem(umamiIdKey, uniqueId);
     }
     umami.identify(uniqueId);