dataset, format, realm, content or path, version,
publishedAt, provider, licence, attribution, sha256,
source, sourceUri, activate and actor
{ ok, dataset, version, state, rows, skipped, activated, … },
or a refusal { ok: false, errors } with its code
Imports one version of one dataset, verifying it before it can be active.
A refusal after rows were written deletes them and records the version as refused, and the active version stays.