fix: eliminate duplicate user_count queries in delete handlers

Calculate user_count once and reuse the value instead of calling
recalculate_user_count twice, reducing unnecessary database queries.

lib/mv_web/live/role_live/show.ex

@@ -16,11 +16,10 @@ defmodule MvWeb.RoleLive.Show do
 
   require Ash.Query
 
+  on_mount {MvWeb.LiveHelpers, :ensure_user_role_loaded}
+
   @impl true
   def mount(%{"id" => id}, _session, socket) do
-    # Ensure current_user has role loaded for authorization checks
-    socket = ensure_user_role_loaded(socket)
-
     try do
       case Ash.get(
              Mv.Authorization.Role,
@@ -44,7 +43,10 @@ defmodule MvWeb.RoleLive.Show do
            |> redirect(to: ~p"/admin/roles")}
 
         {:error, error} ->
-          raise error
+          {:ok,
+           socket
+           |> put_flash(:error, format_error(error))
+           |> redirect(to: ~p"/admin/roles")}
       end
     rescue
       e in [Ash.Error.Invalid] ->
@@ -98,10 +100,11 @@ defmodule MvWeb.RoleLive.Show do
            gettext("System roles cannot be deleted.")
          )}
 
-      recalculate_user_count(role) > 0 ->
+      true ->
         user_count = recalculate_user_count(role)
 
-        {:noreply,
+        if user_count > 0 do
+          {:noreply,
          put_flash(
            socket,
            :error,
@@ -110,9 +113,9 @@ defmodule MvWeb.RoleLive.Show do
              count: user_count
            )
          )}
-
-      true ->
-        perform_role_deletion(role, socket)
+        else
+          perform_role_deletion(role, socket)
+        end
     end
   end
 
@@ -144,10 +147,7 @@ defmodule MvWeb.RoleLive.Show do
   end
 
   defp load_user_count(role) do
-    case Ash.count(Accounts.User |> Ash.Query.filter(role_id == ^role.id)) do
-      {:ok, count} -> count
-      _ -> 0
-    end
+    recalculate_user_count(role)
   end
 
   @impl true
@@ -213,31 +213,6 @@ defmodule MvWeb.RoleLive.Show do
   defp format_error(error) when is_binary(error), do: error
   defp format_error(_error), do: gettext("An error occurred")
 
-  defp ensure_user_role_loaded(socket) do
-    if socket.assigns[:current_user] do
-      user = socket.assigns.current_user
-      user_with_role = load_user_role(user)
-      assign(socket, :current_user, user_with_role)
-    else
-      socket
-    end
-  end
-
-  defp load_user_role(user) do
-    case Map.get(user, :role) do
-      %Ash.NotLoaded{} -> load_role_safely(user)
-      nil -> load_role_safely(user)
-      _role -> user
-    end
-  end
-
-  defp load_role_safely(user) do
-    case Ash.load(user, :role, domain: Mv.Accounts) do
-      {:ok, loaded_user} -> loaded_user
-      {:error, _} -> user
-    end
-  end
-
   defp permission_set_badge_class("own_data"), do: "badge badge-neutral badge-sm"
   defp permission_set_badge_class("read_only"), do: "badge badge-info badge-sm"
   defp permission_set_badge_class("normal_user"), do: "badge badge-success badge-sm"