Description:
Add app restart and re-authentication flow to verify wallet account data persists across sessions.

Background:
The desktop test restarts the app mid-test to verify account persistence. We have AppLifecycleManager infrastructure but haven't integrated it into wallet tests.

Deliverables:

• Integrate AppLifecycleManager.restart_app() into wallet test
• Add re-login flow using WelcomeBackPage
• Verify account created before restart still exists after

Acceptance Criteria:

• App restarts cleanly during test
• User can re-authenticate with password
• Previously created account visible after restart
• Can add second account after restart

References:

• Existing restart usage: test_settings_password_change_password.py
• Coverage matrix features 11-14

Dependencies: Issue 1.1 (edit flow should be done first so we can verify renamed account persists)