SagerNet/sing-box ? reverse-engineered prompt

Build me a universal proxy platform in Go. I'm thinking of a powerful command-line tool that can handle a bunch of different proxy protocols all in one place, kind of like a central hub for all my network traffic.

It should be highly configurable, letting users set up complex routing rules in a single config file. For example, I might want to route traffic to specific websites through one type of proxy, while sending other traffic through a different one. The core idea is to create a single, unified tool that can replace a bunch of other single-purpose proxy clients.

Please make it performant and cross-platform compatible so it can run as a background service on different systems. You can check out how other popular proxy tools are structured for inspiration, but the main goal is creating a flexible and universal platform.