Rearchitect UI test suite for complete, non-flaky coverage against live API

- Migrate Suite4-10, SmokeTests, NavigationCriticalPathTests to AuthenticatedTestCase
  with seeded admin account and real backend login
- Add 34 accessibility identifiers across 11 app views (task completion, profile,
  notifications, theme, join residence, manage users, forms)
- Create FeatureCoverageTests (14 tests) covering previously untested features:
  profile edit, theme selection, notification prefs, task completion, manage users,
  join residence, task templates
- Create MultiUserSharingTests (18 API tests) and MultiUserSharingUITests (8 XCUI
  tests) for full cross-user residence sharing lifecycle
- Add cleanup infrastructure: SuiteZZ_CleanupTests auto-wipes test data after runs,
  cleanup_test_data.sh script for manual reset via admin API
- Add share code API methods to TestAccountAPIClient (generateShareCode, joinWithCode,
  getShareCode, listResidenceUsers, removeUser)
- Fix app bugs found by tests:
  - ResidencesListView join callback now uses forceRefresh:true
  - APILayer invalidates task cache when residence count changes
  - AllTasksView auto-reloads tasks when residence list changes
- Fix test quality: keyboard focus waits, Save/Add button label matching,
  Documents tab label (Docs), remove API verification from UI tests
- DataLayerTests and PasswordResetTests now verify through UI, not API calls

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

iosApp/HoneyDueUITests/Framework/ScreenObjects.swift

@@ -215,7 +215,18 @@ struct LoginScreenObject {
     }
 
     func tapSignUp() {
-        signUpButton.waitUntilHittable(timeout: 10).tap()
+        signUpButton.waitForExistenceOrFail(timeout: 10)
+        if signUpButton.isHittable {
+            signUpButton.tap()
+        } else {
+            // Button may be off-screen in the ScrollView — scroll to reveal it
+            app.swipeUp()
+            if signUpButton.isHittable {
+                signUpButton.tap()
+            } else {
+                signUpButton.forceTap()
+            }
+        }
     }
 
     func tapForgotPassword() {