GetDomain retrieves Domain with the most "important" state.

ScanVersion is the version of the Scan API that the binary is currently using.

On the list.

Requested to be queued, but failed verification.

Queued for addition at next addition date pending continued validation.

Administrator has not yet confirmed their intention to add the domain.

Domain was never submitted, so we don't know.

Domain stores the preload state of a single domain.

Scan stores the result of a scan of a domain.

Token stores the state of an email verification token.

DomainState represents the state of a single domain.