Release a version compatible with cohttp-lwt >= 6.0.0

[The latest `websocket-lwt-unix` version (2.17.0)](https://opam.ocaml.org/packages/websocket-lwt-unix/) has an upper bound dependency `cohttp-lwt-unix >=5.0.0 & <6.0.0~`.

[cohttp-lwt](https://opam.ocaml.org/packages/cohttp-lwt/cohttp-lwt.6.0.0/) has released version 6.0.0 in November, 2024.

Can you please release a new version of `websocket[-lwt-unix]` compatible with cohttp >= 6.0.0? 🙏 