Admin interface for allowed/blocked instances is broken

[Nutomic]

Requirements

• This is a bug report, and if not, please post to https://lemmy.ml/c/lemmy_support instead.
• Please check to see if this issue already exists.
• It's a single bug. Do not report multiple bugs in one issue.
• It's a frontend issue, not a backend issue; Otherwise please create an issue on the backend repo instead.

Summary

Voyager has various allowed instances which show up under /instances:

However the instances tab under /admin only shows a single one.

I suspect this is because the admin ui uses https://voyager.lemmy.ml/api/v4/federated_instances?kind=all which doesnt return all allowed instances in a single api call. It should be changed to make seperate api calls for kind=allowed and kind=blocked, or better yet the /api/v4/site should indicate which one is active. The admin instance list also needs pagination and filter just like /instances (ideally by sharing the same code).

[dessalines]

I'll have to take a look again.