Add pagination to list notes, accounts, and nullifiers

[hackaugusto]

The current version of the endpoints to list notes, accounts, and nullifiers does not have pagination. The best practice is to return a continuation token.

[bobbinth]

An alternative is to remove these endpoints altogether. They were meant solely for testing, but I'm not sure we are using them.

cc @Mirko-von-Leipzig.

[Mirko-von-Leipzig]

If they're not in use then I'm inclined to delete them :). Adding pagination via a continuation token would also be rather simple to implement though.

I assume the wallet/client use the rpc server list, and don't directly access the "internal" store api @igamigo?

[igamigo]

I assume the wallet/client use the rpc server list, and don't directly access the "internal" store api @igamigo?

Correct. These endpoints have been useful in the past for debugging but I don't think they've been used as of recently so I agree it would be good to delete them.

[Mirko-von-Leipzig]

Closed by #608