Confirm the correctness of generated augmented diffs

We are currently running many processes based on minutely augmented diffs. These are generated by a process (overpass-diff-publisher) that is a bit mysterious (possibly furnished by [this repo](https://github.com/mojodna/overpass-diff-publisher)?).

We have observed cases where some users' geometry updates are not appearing in the augmented diff stream. This is a problem, since we are treating the augdiff stream as the authoritative source of truth for our processes. We need to track down how the augdiffs are getting generated, attempt to start a new process to generate said stream from a sufficiently early time, and confirm that the new stream is capturing geometry as it should.

Start by tracing the overpass-diff-publisher process linked in the issue and how it produces the minutely augmented diff stream. Regenerate the stream from a sufficiently early time, then compare it against observed geometry updates. Done means the regenerated augdiffs consistently capture those geometry changes and their correctness is confirmed.

Written by the indexing model from the issue text.