fixed frontent test errors

frontend/vue-app/src/stores/__tests__/auth.childmode.spec.ts

@@ -1,7 +1,12 @@
-import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest'
 import { isParentAuthenticated, isUserLoggedIn, loginUser, initAuthSync } from '../auth'
 import { nextTick } from 'vue'
 
+// Stub window.location to prevent jsdom "navigation to another Document" warnings
+// triggered when the auth store sets window.location.href on logout.
+const locationStub = { href: '', pathname: '/', assign: vi.fn(), replace: vi.fn(), reload: vi.fn() }
+Object.defineProperty(window, 'location', { value: locationStub, writable: true })
+
 // Helper to mock localStorage
 global.localStorage = {
   store: {} as Record<string, string>,