feat(virtualisation): setup modules

modules/nixos/virtualisation/docker.nix

@@ -0,0 +1,32 @@
+{
+  flake.modules.nixos.virtualisation =
+    {
+      config,
+      lib,
+      pkgs,
+      userName,
+      ...
+    }:
+    let
+      cfg = config.tnix.virtualisation;
+    in
+    {
+      options.tnix.virtualisation.docker = {
+        enable = lib.mkEnableOption "Docker container runtime";
+        nvidia = {
+          enable = lib.mkEnableOption "NVIDIA Container Toolkit for Docker";
+        };
+      };
+
+      config = lib.mkIf cfg.docker.enable {
+        virtualisation = {
+          oci-containers.backend = "docker";
+          docker.enable = true;
+        };
+
+        hardware.nvidia-container-toolkit.enable = lib.mkIf cfg.docker.nvidia.enable true;
+        environment.systemPackages = with pkgs; [ lazydocker ];
+        users.users.${userName}.extraGroups = [ "docker" ];
+      };
+    };
+}