add [[bin]] name to Cargo.toml to output prefixed executables

[colemickens]

In the course of packaging this, I noticed that the built binaries are called client, server, and certificate-gen.

For my Nix derivation, I simply prefix them all with rkvm- but I'm wondering if it would be more appropriate to just fix this in the various binaries' Cargo.toml files so that they're automatically named with a prefix.

What do you think?

[colemickens]

I forgot, the other reason this would be nice, I could add the same GitHub action that I added for another Rust project and you'd get Windows binaries attached to a GHA job for each commit. That way you can get more Windows users without them having to build it.

(versus, a zip of "client.exe, server.exe, certificate-gen.exe" might be a bit weird)

[BrendanBall]

This is also the case for cargo install --path server. It ends up putting a binary called server on your path. So I also think it would be great to rename it. I'm not sure if @htrefil might be more responsive if you just open a PR and maybe they'll just merge it

[htrefil]

Fixed.