R1:81a9726fa15c

Make the new "Unverified Email" behavior more clear to other users

Summary:
Ref T12268. Ref T12157. When you mention or interact with a user who is unlikely to be able to respond (for example, because their account is disabled), we try to show a colored dot to provide a hint about this.

Recently, we no longer send any normal mail to unverified addresses. However, the rules for showing a dot haven't been updated yet, so they only care about this if `auth.require-verification` is set. This can be…