Asynchronize Swarm<T> initialization and fix NineChronicles Agent Swarm<T> initialization

[tkiapril]

As of libplanet 0.41.1, initialization of Swarm<T> is not fully asynchronous, and uses Task.GetAwaiter().GetResult() which blocks the main thread and causes context deadlock when used in certain circumstances. As a workaround, in NineChronicles in Init() method in Agent.cs, Swarm<T> initialization is done inside a Task.Run() invocation to isolate the blocking method from the main thread after libplanet 0.41.1 bump. After a API rework, this should be fixed.

The workaround is as follows: from this:

            _swarm = new Swarm<NCAction>(
                blocks,
                privateKey,
                appProtocolVersion: appProtocolVersion,
                host: host,
                listenPort: port,
                iceServers: iceServers,
                differentAppProtocolVersionEncountered: DifferentAppProtocolVersionEncountered,
                trustedAppProtocolVersionSigners: trustedAppProtocolVersionSigners);

To this:

            // FIXME: this should be changed to reflect libplanet API change after it is reworked.
            // For context, refer to https://github.com/planetarium/libplanet/discussions/2303.
            var initSwarmTask = Task.Run(() => new Swarm<NCAction>(
                blocks,
                privateKey,
                appProtocolVersion: appProtocolVersion,
                host: host,
                listenPort: port,
                iceServers: iceServers,
                differentAppProtocolVersionEncountered: DifferentAppProtocolVersionEncountered,
                trustedAppProtocolVersionSigners: trustedAppProtocolVersionSigners));

            initSwarmTask.Wait();
            _swarm = initSwarmTask.Result;

[longfin]

As a workaround, in NineChronicles in Init() method in Agent.cs, Swarm initialization is done inside a Task.Run() invocation to isolate the blocking method from the main thread after libplanet 0.41.1 bump

@tkiapril Could you introduce that workaround here? 🙏

[tkiapril]

Updated the OP!

[longfin]

As commented previously, I still think that we have two choices.

• Introduce new asynchronous factory method other than synchronous constructor
• Admit "unintilalzed state" (😇 again)