expiryYear and expiryMonth are optional.

GetPeeked retrieves the list of peeked coops since the specified time.

GetPeekedGroupedByContract retrieves the list of peeked coops since the specified time, grouped by contract ID.

GetSoloAndCoopStatusesFromRefresh returns contract statuses from the last refresh by the specified cutoff time.

InsertContract upserts the contract into the database.

refreshId is optional, and will be inserted as NULL if zero.

refreshId is optional, and will be inserted as NULL if zero.

Contract is set to nil if no matching contract is found or if there is a database error.

ContractSignature is used to determine contract uniqueness.