Announcing Spegel v0.3.0

Containerd v2.1.0 unlocks a major piece of the puzzle for Spegel. This release removes key limitations that previously held back development. A big part of the work in v0.3.0 has been making sure everything plays well with the new version. That meant refactoring internals and updating the end-to-end tests to run against it. It will take some time before this version makes its way into most cloud…