Support OCI Distribution Spec Extensions

[jay-dee7]

Description

OCI Distribution Spec recently got new additions regarding adding extensions. We already have implemented _catalog extension but now we have support for a model, which allows extending functionality of a container registry in a standardised way.

With this new model, we get ability to add extensions at registry level: /v2/_oci/<extension>
and at repository level: /v2/<name>/_<extension>/<component>/<module>[?query_params]

Docs

• https://github.com/opencontainers/distribution-spec/tree/main/extensions
• https://github.com/opencontainers/distribution-spec/blob/main/extensions/_oci.md