The second in the series of proxy admin service config (see stacked PR!) - this adds the peer listener, so one pod can answer for the whole deployment rather than just itself.

proxyAdmin.peer is where siblings reach this pod. Unlike the operator listener it's on the pod network, so it either needs tls (which verifies the client chain, not just encrypts) or an explicit allowInsecure

There's also discovery, which selects how this pod finds its siblings by name. Only none is accepted for now - dns and static land in the next two PRs.

proxyAdmin:
  listenAddress: "localhost:6061"
  peer:
    listenAddress: "0.0.0.0:6062"
    tls:
      certificatePath: /certs/peer.pem
      keyPath: /certs/peer.key
      remoteCAPath: /certs/ca.pem
      caServerName: s2s-proxy-peers
    discovery:
      provider: none