hosts/ni/networking/setup: open ports 20000-30000 for userland services

It's a long story but this would be great to initialize local services
from different users. Except that there is only one for the most part
anyways.

configs/nixos/ni/modules/networking/setup.nix

@@ -1,4 +1,4 @@
-{ config, lib, pkgs, ... }:
+{ config, lib, pkgs, foodogsquaredLib, ... }:
 
 let
   hostCfg = config.hosts.ni;
@@ -170,6 +170,13 @@ in
           protocols = [ "tcp" ];
           openFirewall = true;
         };
+
+        # This is for user-specific services that would need to be exposed to
+        # the local network.
+        userland = {
+          value = foodogsquaredLib.nixos.makeRange 20000 30000;
+          openFirewall = true;
+        };
       };
     })
   ]);