Extend Redpoint.AutoDiscovery to allow key-value pairs and improve API

[hach-que]

A few things to do here:

• Replace name with ServiceIdentifier and ServiceQuery in INetworkAutoDiscovery.
  • ServiceIdentifier should be readonly record class that has a constructor that takes instanceId and serviceId that generates {instanceId}.{serviceId}._tcp.local, and a static factory method that takes a dnsName that lets you specify the whole thing.
  • ServiceQuery should be a readonly record class that has a constructor that takes serviceId and generates {serviceId}._tcp.local and a static factory method that takes a dnsName that lets you specify the whole thing.
  • This should prevent the easy accident of specifying name is in the wrong format for register/query (since they are slightly different), which leads to no services being discovered on the network.
• Add support for the key-value pairs of DnsServiceConstructInstance in the service instance, and retrieving this information on queries. We want to be able to use this information so that services can advertise public keys in DNS for establishing secure connections.