add ui testing

ui/app/pages/index.spec.ts

@@ -0,0 +1,15 @@
+// @noErrors
+import { it, expect } from 'vitest'
+// ---cut---
+// tests/components/SomeComponents.nuxt.spec.ts
+import { mountSuspended } from '@nuxt/test-utils/runtime'
+import Index from '~/pages/index.vue'
+
+// tests/App.nuxt.spec.ts
+it('can also mount an app', async () => {
+    const component = await mountSuspended(Index, { route: '/test' })
+    expect(component.html()).toMatchInlineSnapshot(`
+      "<h1>Hello World</h1>"
+    `)
+})
+