feat(nix): add firewall rule for HALO system

- Allowed inbound TCP traffic on port 1234 by updating firewall rules.
- Enhances connectivity for the HALO system without altering existing configurations.

systems/x86_64-linux/halo/default.nix

@@ -13,6 +13,10 @@ with lib.metacfg;
   boot.lanzaboote.pkiBundle = "/var/lib/sbctl"; 
   boot.kernelPackages = lib.mkOverride 0 pkgs.linuxPackages_latest;
 
+  networking.firewall.allowedTCPPorts = [
+    1234
+  ];
+
   systemd.tmpfiles.rules = 
   let
     rocmEnv = pkgs.symlinkJoin {