Improve NixOS default firewall declaration

hosts/vm/configuration.nix

@@ -1,4 +1,4 @@
-{ pkgs, ... }:
+{ ... }:
 
 {
   system.stateVersion = "25.05";
@@ -51,6 +51,7 @@
   services.qemuGuest.enable = true;
   services.spice-vdagentd.enable = true;
 
+  networking.firewall.allowedTCPPorts = [ 22 ];
   services.openssh = {
     enable = true;
     harden = true;

modules/networking.nix

@@ -7,8 +7,8 @@
       enable = true;
     };
   };
-  networking.firewall = {
+  networking = {
-    enable = true;
+    nftables.enable = true;
-    allowedTCPPorts = [ 22 ];
+    firewall.enable = true;
   };
 }