Describe the enhancement requested

Due to class protection levels it is not currently possible to implement a flight server outside of AspNet.Core.

i.e. to start a flight server as a non-Kestrel GRPC server the following code can't be used due to protection level of the protocol and FlightServerImplementation classes.

using Apache.Arrow.Flight.Protocol;
using Apache.Arrow.Flight.Server.Internal;

var flightServer = new FlightServerImpl();
var server = new Server
{
    Services = {  FlightService.BindService(new FlightServerImplementation(flightServer)) },
    Ports =  { new ServerPort("0.0.0.0", 5001, ServerCredentials.Insecure) }   }
};
server.Start();

Component(s)

C#, FlightRPC