Investigate: Container registry cleanup policies to live in the container registry (not Rails)

Context

When we first built the cleanup policies for the container registry, we were constrained by the legacy registry which had many performance limitations when it came to finding and removing tags from object storage. But, now that we've launched the next-generation container registry, we have the ability to re-architect the feature so that it has more functionality and better usability.

Problem to solve

Moving the cleanup policies to Rails will allow us to create new APIs for cleanup policies and bulk delete rules that are far more scalable than we currently offer.

Proposal

Investigate how to move the cleanup policies to Rails and build an implementation plan to do so.

Further details

We may have design/UX support for a few milestones. We should revisit our existing designs with a fresh mind knowing that we don't have the same limitations we did in the past.