I was thinking either pinging or some sort of a "check" button that the user would click/tap (e.g. Cloudflare's button to check the status of NS transfers). Not the smoothest part of the idea. This decision would ultimately be left to the consumer of the API. Also, in thinking this through a little more I think it is also applicable to applications that do have their own backend, in which case they could provide a callback.
I like your idea on 3/4. That could maybe be a configurable option
I was thinking either pinging or some sort of a "check" button that the user would click/tap (e.g. Cloudflare's button to check the status of NS transfers). Not the smoothest part of the idea. This decision would ultimately be left to the consumer of the API. Also, in thinking this through a little more I think it is also applicable to applications that do have their own backend, in which case they could provide a callback.
I like your idea on 3/4. That could maybe be a configurable option