`create schema` not supported in iceberg REST catalog API

[chiumichael]

I've successfully attached an iceberg catalog from Cloudflare's R2 as suggested in https://github.com/duckdb/duckdb-iceberg/issues/182 using the code snippet below:

attach '<WAREHOUSE>' as my_catalog (
    TYPE iceberg,
    ENDPOINT <CATALOG_URI>,
    TOKEN <TOKEN>
);

I tried to create a schema/namespace via:

create schema my_catalog.schema;

but got the following error:

Not implemented Error:
IRCAPI::Create Schema not Implemented

Is this the wrong way to go about creating a namespace? Or is this the wrong way to think about Iceberg catalogs, tables, and duckdb? If this is something that's just on the list to be implemented, it would be good to know too.

Thanks!

[Tishj]

Duplicate / part of #37