chore: add @vitest/ui to example

Author: danielroe

examples/app-vitest-full/package.json

@@ -18,6 +18,7 @@
   "devDependencies": {
     "@nuxt/test-utils": "latest",
     "@testing-library/vue": "8.1.0",
+    "@vitest/ui": "3.2.4",
     "happy-dom": "20.0.11",
     "jsdom": "27.4.0",
     "listhen": "1.9.0",