haga-rak/fluxzy.core ? reverse-engineered prompt

Build me a fast MITM proxy tool in C# that can intercept, inspect, record, and modify HTTP 1.1, HTTP 2, WebSocket, and gRPC traffic, even when it’s over TLS.

I want it to work as a command line app, a .NET library, and also be easy to run in Docker. It should support acting as a normal forward proxy, a system proxy, and a reverse proxy, with automatic detection for HTTP CONNECT and SOCKS5 on the same port. Include the ability to manage certificates, export captured sessions to HAR and a Fluxzy style archive, and save decoded packets as PCAP. It should also let me change headers, rewrite request and response bodies, mock responses, block or redirect traffic, and serve static content when needed.

Make it feel polished and practical, with clear defaults and simple setup, and look up current docs online if you need to fill in any missing details.