API Domain change

Hello!

Due to governance changes, we are now using the `realworld.io` domain for the RealWorld demo (both client and API).
Requests from `conduit.productionready.io` are redirected to `api.realworld.io`, but such a redirection might lead to inconsistent responses.

We encourage domain change for the community.
If this repository is maintained anymore, we'll consider hosting a demo of your implementation in a few weeks with the domain change.

The demo link will be added to the RealWorld documentation.

Start by searching the repository for conduit.productionready.io and inspect how the client and API endpoints are configured. Update the relevant domain references to the realworld.io endpoints, then verify that client and API requests no longer depend on the redirected domain.

Written by the indexing model from the issue text.