added vm auto-resizing screens.

roles/nixos/graphical-vm.nix

@@ -0,0 +1,13 @@
+{
+  config,
+  pkgs,
+  lib,
+  ...
+}: {
+  #note: needs to have something that autostarts desktop files.
+  services.spice-vdagentd.enable = true;
+  imports = [
+    ./vm.nix
+  ];
+  host.gui.enable = true;
+}

roles/nixos/vm.nix

@@ -0,0 +1,10 @@
+{
+  config,
+  pkgs,
+  lib,
+  inputs,
+  ...
+}: {
+  services.qemuGuest.enable = true;
+  host.isVm = true;
+}