use coreutils cat in menu command

[phanirithvij]

Describe the bug

devshell/modules/commands.nix

Line 177 in 7c9e793

cat <<'DEVSHELL_MENU'

Here, cat is usually coreutils cat but it should ideally be using ${pkgs.coreutils}/bin/cat instead.

To Reproduce

Steps to reproduce the behavior:

1. Alias cat to bat somewhere
2. save this minimal config in shell.nix

let
  devshell = import (builtins.fetchTarball {
    url = "https://github.com/numtide/devshell/archive/7c9e793ebe66bcba8292989a68c0419b737a22a0.tar.gz";
    sha256 = "sha256:165601skgrlgvgr4h7hjbz80zp7zpn7z2c7qjh6bal8hmjmmlqwi";
  }) { };
in
devshell.mkShell { }

3. run shell via nix-shell
4. bat is used and thus output contains lines etc.

Expected behavior

cat should be used and menu should look normal

System information

• system: "x86_64-linux"
• host os: Linux 6.12.21, NixOS, 25.05 (Warbler), 25.05pre-git
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.27.0pre20250304_271926a
• nixpkgs: /nix/store/fwhfa9pbx8vdi8nd5pcys665baz6xdxf-source

Additional context

• maybe needs to be changed elsewhere too wherever cat is used.
• fortunately works okay with direnv + nix-direnv + use nix so not that affected.
• apologies for making a bugreport instead of a PR