Created headful and headless files for upcoming changes

config/headless.nix

@@ -0,0 +1,21 @@
+# Edit this configuration file to define what should be installed on
+# your system.  Help is available in the configuration.nix(5) man page
+# and in the NixOS manual (accessible by running ‘nixos-help’).
+
+{ config, pkgs, inputs, ... }:
+
+{
+  imports = [
+    ../hardware/vm.nix
+  ];
+
+  # Bootloader.
+  boot.loader.grub.enable = true;
+  boot.loader.grub.device = "/dev/sda";
+  boot.loader.grub.useOSProber = true;
+
+  # Set hostname
+  networking.hostName = "nixos-dev";
+
+  system.stateVersion = "24.05";
+}