- Add MODE_PIPE constant to wsssht.h
- Implement run_pipe_mode() function with proper tunnel negotiation
- Add --pipe and --mode pipe command line options
- Pipe mode negotiates tunnel (tunnel_request -> tunnel_ack) like other modes
- Redirects raw tunnelled data to stdin/stdout instead of binding to TCP ports
- Silent operation with no terminal output
- Compatible with SSH ProxyCommand for transparent WebSocket SSH tunneling
- Update include paths in all affected files after moving headers to libwsssht/
- Update configure.sh to generate correct makefile with new file locations