Save a dataset description as a private draft.

Store a dataset description in your own base. The server does not fetch the source or import its data. Saving creates a managed dataset.md version for base search, collections and OKF export. Existing publication stays unchanged until publish_base. The normal base and document limits apply; extra base capacity uses the existing subscription. Metadata and public discovery have no separate fee. Returns: { base{id,name,visibility,dataset,created_at,updated_at,documents,bytes,api,export_url,okf_url,public_url,embed_url,publication} }