Update to clap@4.0.x

[jessebraham]

Of course, almost immediately after reworking the CLI they had to publish a new major version on us 😁 cargo_toml published an update requiring changes as well, so I've updated it and any other dependencies with new versions.

Unfortunately in this new version of clap they've taken away the possible_values attribute, so I've had to add a simple macro to replace it. This is incredibly unfortunate, but also not the end of the world.

There were also some small issues with our existing structures for the CLI arguments, so I had to address those as well. The --monitor-baud arg should not have been added to ConnectArgs (this was my bad) so I moved it out. Addressed some visual stuff too, just lowercasing options, etc.

Closes #248

[SergioGasquez]

Maybe it's also worth updating the #[clap(...)] attributes with the new derive attributes: https://epage.github.io/blog/2022/09/clap4/#more-specific-derive-attributes

[jessebraham]

Thanks for the link, would be really nice if they had some sort of migration guide or something. Half of the issues I ran into i only fixed because I spent a bunch of time searching through the issues and discussions in their repository 😅 Looks like there are a few things I should update though so I'll get that done shortly!