Build the full client half of docs/api/push-notifications-integration-guide.md:
OS permission + APNs device-token registration and pipeline wiring, profile
notifications/biometric-login toggles on the Ver Perfil screen reflecting
server truth, order-tracking opt-in fallback prompt, profile-cache refresh
on every mutation, a Notification Service Extension for rich/image push,
the Push Notifications capability, targeting-attributes sync, campaign open
tracking, and tap-to-order deep linking with foreground notification display.
