feat: enhance vacation management system with new employee association functionality, improved email notification handling, and comprehensive documentation; update dependencies and UI components for better user experience

apps/web/src/routes/(dashboard)/+layout.svelte

@@ -1,6 +1,7 @@
 <script lang="ts">
   import { page } from "$app/state";
   import MenuProtection from "$lib/components/MenuProtection.svelte";
+  import { Toaster } from "svelte-sonner";
   
   const { children } = $props();
   
@@ -82,3 +83,6 @@
     {@render children()}
   </main>
 {/if}
+
+<!-- Toast Notifications (Sonner) -->
+<Toaster position="top-right" richColors closeButton expand={true} />