[Feature Request]: Allow to chain ssserver to another socks5 proxy

Please allow to chain shadowsocks server to another socks proxy.

For example user wants to connect to a cloudflare Warp gateway (which is in socks5 proxy mode) but to have his side using shadowsocks (on windows). Currently shadowsocks-windows do not allow to configure tunnel protocol. This prevents such scheme.

So it would allow to use usual shadowsocks windows client (as a socks proxy) that connects as normal to a remote ssserver but that ssserver redirects (not decoded socks5 traffic) to a local warp-server socks5 port.