Tagger tag adjustment API enhancements

[davenquinn]

Right now, POSTing new tags to the tagger API accepts a single tagger parameter alongside a list of tags. This makes sense for new tag additions, where we want to ensure that tags all have the right user created.

However this API route fails when we are adjusting already-saved tags. When we pass a different tagger than the tag was initially saved by, we end up creating duplicates. In PR #65, we solve this using a frontend hack of setting the tagger parameter to the value returned for the first tag. This works fine, but only if all tags were created by the same user.

I propose that the tagger app API be modified to optionally accept a tagger, ignore the tagger parameter provided if it conflicts with a previous value, or to simply overwrite the old tag with the new one tied to the new tagger. Either way, we shouldn't duplicate tags on edit.

I don't actually know where that code lives now, so i can't make this a PR in the correct place.

[github-actions]

This issue is stale because it has been open for 60 days with no activity.