Set up sops-nix.

nodes/hosts/common/configuration.nix

@@ -4,6 +4,7 @@
     inputs.nix-flatpak.nixosModules.nix-flatpak
     inputs.stylix.nixosModules.stylix
     inputs.home-manager.nixosModules.home-manager
+    inputs.sops-nix.nixosModules.sops
     ./programs/emulation.nix
     ./programs/firefox.nix
     ./programs/fonts.nix

nodes/hosts/common/programs/general.nix

@@ -22,6 +22,7 @@
     pkgs.elinks
     pkgs.fastfetch
     pkgs.git
+    pkgs.gnumake
     pkgs.gpustat
     pkgs.hdrop
     pkgs.htop