Add usbguard service

Signed-off-by: Hadi <112569860+anotherhadi@users.noreply.github.com>

nixos/usbguard.nix

@@ -0,0 +1,7 @@
+{config, ...}: {
+  services.usbguard = {
+    enable = true;
+    implicitPolicyTarget = "block";
+    IPCAllowedUsers = ["root" config.var.username];
+  };
+}