feat: cb loop csharp bindings (#587)

* fix: make benchmarks compatable with windows

* double include

* fix valgrind ubuntu

* feat: cb loop csharp bindings

* clang

* address comments: basic usage and nullptr throw

---------

Co-authored-by: zwd-ms <71728747+zwd-ms@users.noreply.github.com>

bindings/cs/rl.net.cli.test/CMakeLists.txt

@@ -1,7 +1,9 @@
 set (RL_NET_CLI_TEST_SOURCES
   CleanupContainer.cs
+  MockSender.cs
   ReplayStepProviderTest.cs
   SenderExtensibilityTest.cs
+  SenderExtensibilityCBLoopTest.cs
   TempFileDisposable.cs
   TestBase.cs
   UnicodeTest.cs

bindings/cs/rl.net.cli.test/MockSender.cs

@@ -0,0 +1,70 @@
+using System;
+using System.Diagnostics;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+using Rl.Net;
+using Rl.Net.Native;
+
+namespace Rl.Net.Cli.Test
+{
+    using SenderFactory = Func<IReadOnlyConfiguration, ErrorCallback, ISender>;
+    using BackgroundErrorCallback = Action<ApiStatus>;
+
+    internal class MockSender : ISender
+    {
+        public Action<ApiStatus> Init
+        {
+            get;
+            set;
+        }
+
+        public Action<SharedBuffer, ApiStatus> Send
+        {
+            get;
+            set;
+        }
+
+        void ISender.Init(ApiStatus status)
+        {
+            if (this.Init != null)
+            {
+                this.Init(status);
+            }
+        }
+
+        void ISender.Send(SharedBuffer buffer, ApiStatus status)
+        {
+            if (this.Send != null)
+            {
+                this.Send(buffer, status);
+            }
+        }
+    }
+
+
+    internal class MockAsyncSender : AsyncSender
+    {
+        public MockAsyncSender(ErrorCallback callback) : base(callback)
+        {
+        }
+
+        public new Func<SharedBuffer, BackgroundErrorCallback, Task> Send
+        {
+            get;
+            set;
+        }
+
+        protected override Task SendAsync(SharedBuffer buffer)
+        {
+            if (this.Send != null)
+            {
+                return this.Send(buffer, this.RaiseBackgroundError);
+            }
+
+            return Task.CompletedTask;
+        }
+    }
+}