This is a bit messy, but not tooo bad:
- In general, stop the author from being added as a reviewer.
- In the specific case that "self accept" is enabled, allow it. This is easier than trying to special case it.
- When commandeering, we make the author a reviewer and make the actor the author, but these happen after validation. At validation time, it looks like we're making the author a reviewer. Just special case this.
- Provide a slightly nicer message when trying to add yourself from arc. We hit the Transactions message anyway, but it's not formatted as cleanly.
- Don't try to add the author via Herald.