I am looking for a way to do authentication provider chaining with keycloak. Basically, I want to have multiple authentication providers, example username, Suregrid etc. On submitting username, we call a service and if that service tells us to use SureGrid, then we should be able to pass control to the corresponding authentication provider. So basically, I want to spilt one authentication provider into multiple and be able to chain them based on the response from the service called. I have not found any documentation that explains this. Could you suggest how to achieve this?