Add Fuzz Testing

[nGoline]

Implement Fuzz Tests on the project. Our best option seems to be SharpFuzz.

Over the weekend a group won a hackathon at the bitcoin++ conference, thanks to a differential fuzz that found a bug on NLightning.

Please, let me know as soon as you start working on this issue so I can plan my work based on other issues.

[thgO-O]

I'll take this on and start implementing fuzz tests with SharpFuzz.

[nGoline]

@thgO-O I was looking at your implementation and it feels, at least superficially, that it's not a huge refactor to rebase this PR to main.

Let me know If you need help so we can get in a call to discuss it. If you think you cannot continue working on this issue, let us know so other people can take over this work.