feat(sessions): per-subscriber backpressure isolation in SessionEventDistributor

src/ZB.MOM.WW.MxGateway.Tests/Gateway/Sessions/GatewaySessionTests.cs

@@ -3,6 +3,7 @@ using Microsoft.Extensions.Logging.Abstractions;
 using ZB.MOM.WW.MxGateway.Contracts.Proto;
 using ZB.MOM.WW.MxGateway.Server.Configuration;
 using ZB.MOM.WW.MxGateway.Server.Grpc;
+using ZB.MOM.WW.MxGateway.Server.Metrics;
 using ZB.MOM.WW.MxGateway.Server.Sessions;
 using ZB.MOM.WW.MxGateway.Server.Workers;
 
@@ -260,7 +261,8 @@ public sealed class GatewaySessionTests
                 new MxAccessGrpcMapper(),
                 new EventOptions { QueueCapacity = 8 },
                 NullLogger<SessionEventDistributor>.Instance,
-                TimeProvider.System));
+                TimeProvider.System,
+                new GatewayMetrics()));
         session.AttachWorkerClient(workerClient);
         session.MarkReady();
         return session;