Label the NTC events with the local peer identifier

@Infinisil noticed that the `localPeer` type parameter for `Ouroboros.Consensus.Node.Tracers.Tracers'` isn't used at all.

This Issue is to add the `TraceLabelPeer localPeer` wrapper to the Node-to-Client events in order to match the existing `TraceLabelPeer remotePeer` wrapper on the Node-to-Node events.

We're thinking that under normal circumstances, there's probably only one (main?) local peer: the wallet. But that's not necessarily the case. So this currently-missing label could be a helpful disambiguator in some scenarios.