mirror add-peer, run on the mirror's machine, sets up a mirror on
another over ssh, kept in step with this one: llmgw there if it has
none, mirror init --peer, this mirror told of it and allowed to be read
by it, and mirror.peers in the cluster's settings. The setup screens
offer one on either database machine, as server init --second-mirror.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>