Summary

This PR introduces a proof-of-concept C#/.NET port of key Apache Kafka client classes, demonstrating a modern .NET approach and project structure for a potential full conversion.

Details

• Added .NET solution and projects for Kafka.Common, Kafka.Clients, Kafka.Core, Kafka.Streams, and Kafka.Tests.
• Converted core Java client classes: ClientRequest, ClientResponse, IRequestCompletionHandler, and related protocol/exception types to C#.
• Implemented an idiomatic generic IProducer<TKey, TValue> interface, ProducerRecord, and RecordMetadata for .NET.
• Included a sample application (SimpleProducer) demonstrating API usage (interface only).
• Added xUnit tests for ClientRequest class to verify correctness.
• Provided a comprehensive README-CSHARP-PORT.md explaining the proof-of-concept, architecture decisions, and the challenges of a full conversion.
• Ensured the project builds and passes all unit tests on .NET 8.0.

Warning: Task VM test is not passing, Engine will perform much better if you fix the setup