test: fix test warnings and flakiness

- Add createStackPlugin isolation to Dialog tests to prevent
  "Ticket already exists" warnings from shared singleton
- Remove redundant onboard() call in useDiscovery test
- Fix empty app component warning in useFeatures tests
- Suppress expected console.warn calls in validation tests
  (useHotkey, createNested, Avatar renderless, useBreakpoints)
- Increase testTimeout to 20s across all vitest configs to
  prevent intermittent timeouts under parallel load

Author: johnleider

apps/docs/src/composables/useDiscovery/index.test.ts

@@ -678,9 +678,6 @@ describe('useDiscovery', () => {
       discovery.complete()
       expect(discovery.isComplete.value).toBe(true)
 
-      // Need to start again since complete() sets isActive to false
-      discovery.tours.onboard([mockTour as any])
-
       discovery.reset()
 
       expect(discovery.isComplete.value).toBe(false)

apps/docs/vitest.config.ts

@@ -24,5 +24,6 @@ export default defineConfig({
     environment: 'happy-dom',
     globals: true,
     include: ['**/*.{test,spec}.?(c|m)[jt]s?(x)'],
+    testTimeout: 20_000,
   },
 })

packages/0/src/components/Avatar/index.test.ts

@@ -359,6 +359,10 @@ describe('avatar', () => {
 
     describe('renderless mode', () => {
       it('should support renderless mode with slot props', () => {
+        // Suppress Vue warning about runtime directive on non-element root
+        // This is expected when using v-show with renderless components
+        const warnSpy = vi.spyOn(console, 'warn').mockImplementation(() => {})
+
         let slotProps: any
 
         const wrapper = mount(Avatar.Root, {
@@ -375,6 +379,8 @@ describe('avatar', () => {
 
         expect(slotProps).toBeDefined()
         expect(wrapper.find('.custom-img').exists()).toBe(true)
+
+        warnSpy.mockRestore()
       })
     })
   })