add nr to rebuild nixos and darwin

modules/darwin/utilities.nix

@@ -37,6 +37,13 @@
 
     xdg.configFile.hammerspoon = { source = ./hammerspoon; };
 
+    programs.fish = {
+      shellAbbrs = {
+        nr =
+          "sudo darwin-rebuild switch --flake ${config.dotfilesPath}#macbook";
+      };
+    };
+
   };
 
   system.activationScripts.hammerspoon.text = ''