feat: add inital in memory dispatcher

Add a simple in memory dispatcher for scalar requests and stream request.

src/request.tests/_fixtures/StreamOrderingOpenBehavior.cs

@@ -0,0 +1,14 @@
+// Copyright (c) The Geekeey Authors
+// SPDX-License-Identifier: EUPL-1.2
+
+namespace Geekeey.Request.Tests;
+
+public class StreamOrderingOpenBehavior<TRequest, TOutput>(StreamTestTracker tracker) : IStreamRequestBehavior<TRequest, TOutput>
+where TRequest : IStreamRequest<TOutput>
+{
+	public IAsyncEnumerable<TOutput> HandleAsync(TRequest request, StreamHandlerDelegate<TOutput> next, CancellationToken cancellationToken)
+	{
+		tracker.Log.Add("Open");
+		return next(request, cancellationToken);
+	}
+}