Find out how to distribute GHCiTUI

Currently the only installation process is to install from source as a Nix-style build. This is probably okay if the package is available on Hackage, but it's a bit limiting. See if we can get a standalone executable build working that we can ship from a tarball? Ideally, I would like to not ship our own libc, so perhaps worth looking into what linking configurations we can configure.

May need to make a Setup.hs script too. Can't find a huge amount of documentation for what that actually implies beyond the Cabal manual (https://cabal.readthedocs.io/en/stable/setup-commands.html)

Start with the current Nix-style source installation and the Cabal manual linked in the issue, then investigate whether a Setup.hs script and suitable linking configurations can produce a standalone build. Done means documenting or implementing a way to ship GHCiTUI as an executable in a tarball without bundling its own libc.

Written by the indexing model from the issue text.