Updated to NixOS 24.11 (MfGames Writing Setup Flake)

An occasional chores, we've updated the flake to be based off NixOS 24.11. From our understanding, the flake input could always be changed but this sets up a nice default using the current, non-deprecated version of NixOS.

Along with this, we've also updated to the latest version of mfgames-project-setup-flake which does the same thing (and copies the same first paragraph as this post).