Peer mode is active.

Common commands:
- `/peer start <prompt>` starts a background peer.
- `/peer ask <name> | <message>` waits for a reply.
- `/peer send <name> | <message>` sends fire-and-forget work.
- `/peer list` shows peers and current state.
- `/peer history <name>` scrolls a peer transcript.
- `/peer models` shows model ids and aliases.
- `/peer dashboard` opens the peer dashboard.
- `/peer help` shows full command help.