Can you add the X-WP-* fields from the header to the corresponding object?

[ajo2995]

To determine how many pages of data are available, the API returns two header fields with every paginated response:

X-WP-Total: the total number of records in the collection
X-WP-TotalPages: the total number of pages encompassing all available records

By inspecting these header fields you can determine how much more data is available within the API.

https://developer.wordpress.org/rest-api/using-the-rest-api/pagination/