[push/opt-in-prompts] Implement push notifications client integration

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.

Sources/PediFoods/Services/SessionStateStore.swift

@@ -88,6 +88,19 @@ enum SessionStateStore {
     private static let pendingCartOrderKeyPrefix = "session.cart.pending-order.v1."
     private static let orderReviewsKeyPrefix = "session.orders.reviews.v1."
     private static let orderReviewDraftKeyPrefix = "session.orders.review-draft.v1."
+    private static let pushOptInPromptKey = "session.push.opt-in.last-prompted.v1"
+    private static let pushOptInCooldown: TimeInterval = 60 * 60 * 24
+
+    /// See docs/api/push-notifications-integration-guide.md §2b — avoid
+    /// re-prompting the order-tracking fallback alert on every screen visit.
+    static func shouldPromptPushOptIn() -> Bool {
+        guard let last = UserDefaults.standard.object(forKey: pushOptInPromptKey) as? Date else { return true }
+        return Date().timeIntervalSince(last) > pushOptInCooldown
+    }
+
+    static func recordPushOptInPrompted() {
+        UserDefaults.standard.set(Date(), forKey: pushOptInPromptKey)
+    }
 
     static func makeUserKey(profileId: String?, email: String?) -> String? {
         let id = (profileId ?? "")