Fix UI test failures: registration dismiss cascade, onboarding reset, test stability

- Fix registration flow dismiss cascade: chain fullScreenCover → sheet onDismiss
  so auth state is set only after all UIKit presentations are removed, preventing
  RootView from swapping LoginView→MainTabView behind a stale sheet
- Fix onboarding reset: set hasCompletedOnboarding directly instead of calling
  completeOnboarding() which has an auth guard that fails after DataManager.clear()
- Stabilize Suite1 registration tests, Suite6 task tests, Suite7 contractor tests
- Add clean-slate-per-suite via AuthenticatedUITestCase reset state
- Improve test account seeding and screen object reliability

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

iosApp/HoneyDueTests/DataManagerExtendedTests.swift

@@ -42,7 +42,9 @@ extension DataLayerTests {
                 iconAndroid: "",
                 tags: tags,
                 displayOrder: 0,
-                isActive: true
+                isActive: true,
+                regionId: nil,
+                regionName: nil
             )
         }