ginuerzh/gost ? reverse-engineered prompt

Build me a simple but powerful secure tunnel app in Go that can run as a local proxy and forward traffic to other servers. I want it to support HTTP, HTTPS, HTTP2, SOCKS5, Shadowsocks, SSH, QUIC, and KCP, plus local and remote port forwarding for both TCP and UDP. It should also handle transparent proxying, DNS forwarding, SNI based routing, load balancing, access control, and simple auth for proxy access.

Please make it easy to run from the command line with flags for listening ports and forwarding chains, so I can chain multiple proxies together. If possible, include support for TLS, custom certificates, and the usual examples in the README so I can quickly try things like a local SOCKS5 proxy, a tunneled HTTP2 connection, or forwarding port 2222 to an SSH server. Use the existing Go codebase and look up current docs online if you need to.