Feature Request / Improvement

The REST Catalog has support for server side planning: https://github.com/apache/iceberg/blob/68a241615e104d97a86c932c381d7dfac802d769/open-api/rest-catalog-open-api.yaml#L605

We can take the relevant objects from the open-api generated code: https://github.com/apache/iceberg/blob/68a241615e104d97a86c932c381d7dfac802d769/open-api/rest-catalog-open-api.py#L1422