Fix firewall and add back leash while I figure out why disko is failing

hosts/leash/default.nix

@@ -0,0 +1,15 @@
+{ ... }:
+{
+  imports = [
+    ./boot
+    ./disko
+    ./hardware
+    ../../modules/system
+  ];
+
+  system.lanzaboote.enable = true;
+  system.wireguard.client.enable = false;
+  system.video.nvidia.enable = true;
+
+  networking.hostName = "leash";
+}