APNS Push Notification Structure for Firebase Deep Links

My question is about the APNS push notification data structure that is used behind the scenes for Firebase when triggering a push notification. Specifically, it's about the deep link that Firebase uses for its dynamic URLs that opens an application in a specific view.

The structure of the dynamic URL looks something like https://your_subdomain.page.link/?link=your_deep_link&apn=package_name[&amv=minimum_version][&afl=fallback_link] . My understanding is that Firebase must eventually send an APNS push that goes to the receiving iOS application in the end. Somewhere in the sent data structure there must be the information contained in this URL.

The default APNS data structure looks something like:

{
    "aps": {
        "alert": {
            "body": "My message"
        },
        "badge": 1,
        "sound": "default"
    }
}

Where in this structure does the Firebase dynamic link information go?