Greydus/Rabbit ? reverse-engineered prompt

Build me a small C# app from the code that is already here, and make it easy to run from the command line.

I want the project to compile cleanly, start up without errors, and feel like a finished little tool instead of a rough demo. If anything is missing, fill in the blanks in a sensible way based on the existing Program.cs, and keep the code simple and readable. Add any helpful setup or usage notes so I can understand how to run it right away.

If you need to check current docs or best practices online, go ahead and do that. Please keep the scope modest, focus on making the existing app work well, and don’t add extra complexity unless it clearly helps.