Lemmy data replication - a "backfill" tool to identify missing posts and comments to try and trigger copy of missing data between servers

If anyone is working on such a tool, please speak up. I've got some clumsy Javascript code in the form of a SvelteKit app I named "lemmy_helper" that I am thinking of adding this as a command line where you can put in the URL of two servers for a specific community and crawl postings and comments and try to discover missing ones.

As I understand it, the Federation protocols have no 'bulk copy' ability, no way to send a list of comments and postings and get them all at once. So each individual missing comment and posting would need to be triggered by a search on the server that is missing them?

I propose "lemmy-remote-data-repair" as the working name for this concept code/app.