refactor: Use submit_form wrapper in all LiveView forms

- Replace AshPhoenix.Form.submit with submit_form/3 wrapper
- Import current_actor and submit_form from LiveHelpers
- Consistent actor handling in all form submissions

lib/mv_web/live/membership_fee_settings_live.ex

@@ -63,7 +63,9 @@ defmodule MvWeb.MembershipFeeSettingsLive do
         Map.put(params, "include_joining_cycle", false)
       end
 
-    case AshPhoenix.Form.submit(socket.assigns.form, params: normalized_params) do
+    actor = MvWeb.LiveHelpers.current_actor(socket)
+
+    case MvWeb.LiveHelpers.submit_form(socket.assigns.form, normalized_params, actor) do
       {:ok, updated_settings} ->
         {:noreply,
          socket