chore: allow two storage versions

[TimoGlastra]

As discussed during the Credo WG call, this PR allows the last two storage versions to be used. This means you can already update to Credo 0.6, and then run the migration at a later stage. Not updating immediately may impact some behaviour (especially if you rely on new features), but we aim to support two storage versions.

Still draft as I need to update existing and add new tests. But I was surprised that the logic to support two versions was quite simple.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 887d9c9

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR