[push-deeplink-routing-contract] Generalize push tap routing to DeepLinkDestination

Replace order_status-only NotificationCenter path with a single
DeepLinkDestination enum + PushDeepLinkParser, decoded once in
PushNotificationCoordinator and dispatched via ContentView.route(to:).
Also fixes NotificationService reading userInfo["image"] instead of
the guide's stale "imageUrl" key.

Darwin/NotificationServiceExtension/NotificationService.swift

@@ -2,7 +2,9 @@ import UserNotifications
 
 /// Rich (image) push — see docs/api/push-notifications-integration-guide.md §4.3.
 /// Only fires when Atomenta's push payload sets `"mutable-content": 1`, which
-/// it does by default on any push carrying an `imageUrl`.
+/// it does by default on any push carrying an image (real wire key is
+/// `"image"`, not the guide's `"imageUrl"` — verified against
+/// `PushNotificationService.dispatchApns`/`dispatchApnsMany` in Atomenta).
 /// `@unchecked Sendable`: the extension process only ever runs one
 /// `didReceive`/`serviceExtensionTimeWillExpire` cycle at a time — there's no
 /// real concurrent access to `contentHandler`/`bestAttemptContent` to guard
@@ -17,7 +19,7 @@ final class NotificationService: UNNotificationServiceExtension, @unchecked Send
         let mutableContent = (request.content.mutableCopy() as? UNMutableNotificationContent) ?? UNMutableNotificationContent()
         bestAttemptContent = mutableContent
 
-        guard let imageURLString = request.content.userInfo["imageUrl"] as? String,
+        guard let imageURLString = request.content.userInfo["image"] as? String,
               let imageURL = URL(string: imageURLString) else {
             deliver()
             return