Add svelte-sonner for notifications and enhance employee search functionality

- Integrated svelte-sonner for toast notifications in the layout.
- Implemented server-side search for employees with pagination in the API.
- Updated employee loading logic to support search queries and loading more results.
- Enhanced employee detail view with navigation and improved UI interactions.
- Adjusted cookie handling in hooks for PocketBase authentication.

package.json

@@ -32,6 +32,7 @@
 	"dependencies": {
 		"clsx": "^2.1.1",
 		"pocketbase": "^0.26.8",
+		"svelte-sonner": "^1.0.7",
 		"tailwind-merge": "^3.4.1"
 	}
 }