refactor: Replace actor option patterns with ash_actor_opts helper

- Replace if actor, do: [actor: actor], else: [] with Mv.Helpers.ash_actor_opts/1
- Update email_sync/loader.ex, member validations, member.ex, cycle_generator.ex
- Consistent actor handling across non-LiveView modules

lib/membership/member.ex

@@ -39,6 +39,7 @@ defmodule Mv.Membership.Member do
 
   require Ash.Query
   import Ash.Expr
+  alias Mv.Helpers
   require Logger
 
   alias Mv.Membership.Helpers.VisibilityConfig
@@ -1217,7 +1218,7 @@ defmodule Mv.Membership.Member do
   # Extracts custom field values from existing member data (update scenario)
   defp extract_existing_values(member_data, changeset) do
     actor = Map.get(changeset.context, :actor)
-    opts = if actor, do: [actor: actor], else: []
+    opts = Helpers.ash_actor_opts(actor)
 
     case Ash.load(member_data, :custom_field_values, opts) do
       {:ok, %{custom_field_values: existing_values}} ->