Issue #22: implement pipe client and frame protocol

src/MxGateway.Worker/Ipc/WorkerFrameProtocolException.cs

@@ -0,0 +1,25 @@
+using System;
+
+namespace MxGateway.Worker.Ipc;
+
+public sealed class WorkerFrameProtocolException : Exception
+{
+    public WorkerFrameProtocolException(
+        WorkerFrameProtocolErrorCode errorCode,
+        string message)
+        : base(message)
+    {
+        ErrorCode = errorCode;
+    }
+
+    public WorkerFrameProtocolException(
+        WorkerFrameProtocolErrorCode errorCode,
+        string message,
+        Exception innerException)
+        : base(message, innerException)
+    {
+        ErrorCode = errorCode;
+    }
+
+    public WorkerFrameProtocolErrorCode ErrorCode { get; }
+}