Add onboarding UI tests and improve app data management

- Add Suite0_OnboardingTests with fresh install and login test flows
- Add accessibility identifiers to onboarding views for UI testing
- Remove deprecated DataCache in favor of unified DataManager
- Update API layer to support public upgrade-triggers endpoint
- Improve onboarding first task view with better date handling
- Update various views with accessibility identifiers for testing
- Fix subscription feature comparison view layout
- Update document detail view improvements

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

iosApp/CaseraUITests/UITestHelpers.swift

@@ -43,6 +43,13 @@ struct UITestHelpers {
                 }
             }
         }
+        
+        // if user is on verify screen after previous test
+        let logoutButton = app.buttons.containing(NSPredicate(format: "label CONTAINS[c] 'Logout'")).firstMatch
+        if logoutButton.exists {
+            logoutButton.tap()
+            sleep(2)
+        }
 
         // Verify we're back on login screen
         XCTAssertTrue(welcomeText.waitForExistence(timeout: 5), "Failed to log out - Welcome Back screen should appear after logout")