kAFL/Nyx alignment

The goal of this issue is to spark the discussion on the current state of kAFL compared to the [Nyx project](https://github.com/nyx-fuzz), how we might want to align kAFL to match Nyx's future evolutions.

# TODO

- [x] Generate `cargo doc` documentation for [libnyx](https://github.com/nyx-fuzz/libnyx) (see attachments: [libnyx_doc.zip](https://github.com/IntelLabs/kAFL/files/11406091/libnyx_doc.zip))
- [x] ensure libnyx can be compiled (https://github.com/nyx-fuzz/libnyx/pull/21, https://github.com/nyx-fuzz/libnyx/pull/20)
- [ ] Document kAFL's fuzzer interface to QEMU ([`qemu_aux_buffer.py`](https://github.com/IntelLabs/kafl.fuzzer/blob/master/kafl_fuzzer/worker/qemu_aux_buffer.py), ...)
- [ ] Document differences between kAFL and Nyx project
- [ ] Sketch out a new design for libnyx API
- [ ] Collect requirements from all possible use cases, and consider future evolutions
- [ ] How to propagate kafl configuration to libnyx
- [ ] Hold design session

cc @schumilo for the brainstorming