Improve gateway reliability and dashboard docs

src/MxGateway.Worker.Tests/Ipc/WorkerPipeClientTests.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.IO;
 using System.IO.Pipes;
 using System.Threading;
@@ -228,6 +229,21 @@ public sealed class WorkerPipeClientTests
                 currentCommandCorrelationId: string.Empty);
         }
 
+        public IReadOnlyList<WorkerEvent> DrainEvents(uint maxEvents)
+        {
+            return Array.Empty<WorkerEvent>();
+        }
+
+        public WorkerFault? DrainFault()
+        {
+            return null;
+        }
+
+        public bool CancelCommand(string correlationId)
+        {
+            return false;
+        }
+
         public void RequestShutdown()
         {
         }