What would you like to be added:

Archivist is an open-source attestation store. It would give users another way to interact with Syft attestations.

Why is this needed:

Currently, they only way to interact with DSSE attestations is through an OCI registry.

Additional context:
Archivist has an easy to use endpoint to upload attestations and a public instance at archivist.testifysec.io

https://github.com/testifysec/archivist