Add helper functions for multi-user toggle support

Introduced a new file `lib.nix` containing helper functions to streamline user package management and attributes for multi-user configurations. Updated various modules to utilize these functions, enhancing code maintainability and readability.

modules/factories/mkscript.nix

@@ -37,13 +37,11 @@
   };
   config = lib.mkIf (lib.any (s: s.enable) (lib.attrValues config.my.scripts)) {
     users.users = let
-      users = if lib.isString config.my.toggleUsers.scripts then [ config.my.toggleUsers.scripts ] else config.my.toggleUsers.scripts;
+      userLib = import ../lib.nix { inherit lib; };
       packages = config.my.scripts
         |> lib.mapAttrsToList (_name: script: lib.optional (script.enable && script.install) script.package)
         |> lib.flatten;
-    in lib.mkMerge (map (user: {
-      ${user}.packages = packages;
-    }) users);
+    in userLib.mkUserPackages config.my.toggleUsers.scripts packages;
     systemd.user.services =
       config.my.scripts
       |> lib.mapAttrs' (