Customers have reported confusion about how archived changesets factor into the batch change overall completion percentage. Presently, archived is treated as incomplete, but this doesn't make much sense given what archived actually means. If a changeset is archived, it means the repo no longer matched the on: statement in the batch spec. The PR is closed but kept associated with the batch change for the purposes of maintaining a historical record. With this meaning for context, it makes more sense to exclude archived changesets from the completion percentage calculation altogether, as we do with deleted changesets.

We should also consider clarifying how the completion percentage is computed with a tooltip from the UI.