Refactor home modules and update printing comments

Add placeholder publishing settings in printing module.

Refactor Codex module to add nodejs to home packages and nest the
program configuration under `config`. Simplify Opencode validation by
removing the TUI validation flag, keeping only `config`.

modules/core/printing.nix

@@ -28,6 +28,11 @@
         enable = true;
         userServices = true;
       };
+      # settings.publish = {
+      #   disable-publishing = false;
+      #   disable-user-service-publishing = false;
+      #   publish-adresses = true;
+      # };
     };
 
     ipp-usb.enable = true;