feat(ui): add global feedback and agent menu

src/routes/+layout.svelte

@@ -1,6 +1,7 @@
 <script lang="ts">
 	import '../app.css';
 	import AppShell from '$lib/components/AppShell.svelte';
+	import ToastViewport from '$lib/components/ToastViewport.svelte';
 	let { data, children } = $props();
 </script>
 
@@ -9,3 +10,4 @@
 </svelte:head>
 
 <AppShell user={data.user} isacAccess={data.isacAccess} notificationSummary={data.notifications}>{@render children()}</AppShell>
+<ToastViewport/>