Registration is a government filing. A vault is not.
Copyright can exist without registration. For many U.S. works, registration is required before suing. Timely registration can affect statutory damages and fees.
Registration is filed through the U.S. Copyright Office. Typical online fees are $45–$65, depending on the application. Fees change, so check copyright.gov.
Session Copy does not file registrations or sell “official copyright.”
A hash + UTC receipt records when Session Copy received a file. It is not registration or proof of authorship.