feat(limonka): stuff

Disable `himalaya` (not using, compiles a long time)
Add `nushell` as a system package

modules/nix-darwin/system/default.nix

@@ -21,7 +21,14 @@ in
     services.nix-daemon.enable = true;
     # programs.nix-index.enable = true;
 
-    environment.shells = [ pkgs.zsh ];
+    environment.systemPackages = [
+      pkgs.zsh
+      pkgs.nushell
+    ];
+    environment.shells = [
+      pkgs.zsh
+      pkgs.nushell
+    ];
 
     security.pam.enableSudoTouchIdAuth = true;