misc improvements to modularity

modules/features/nixos/home-manager.nix

@@ -20,7 +20,7 @@
         inherit inputs;
       };
 
-      users.grey = self.homeModules.${config.info.hostName};
+      users.${config.info.userName} = self.homeModules."${config.info.userName}@${config.info.hostName}";
     };
   };
 }