Member/Setting/validations: domain, actor, and seeds

- setting.ex: domain/authorize for default_membership_fee_type_id check
- validate_same_interval: require membership_fee_type (no None)
- set_membership_fee_start_date: domain/actor for fee type lookup
- Validations: domain/authorize for cross-resource checks
- helpers.ex, email_sync change, seeds.exs actor/authorize fixes
- Update related tests

lib/mv/accounts/user/validations/email_not_used_by_other_member.ex

@@ -81,7 +81,7 @@ defmodule Mv.Accounts.User.Validations.EmailNotUsedByOtherMember do
     query =
       Mv.Membership.Member
       |> Ash.Query.filter(email == ^to_string(email))
-      |> maybe_exclude_id(exclude_member_id)
+      |> Mv.Helpers.query_exclude_id(exclude_member_id)
 
     system_actor = SystemActor.get_system_actor()
     opts = Helpers.ash_actor_opts(system_actor)
@@ -101,7 +101,4 @@ defmodule Mv.Accounts.User.Validations.EmailNotUsedByOtherMember do
         :ok
     end
   end
-
-  defp maybe_exclude_id(query, nil), do: query
-  defp maybe_exclude_id(query, id), do: Ash.Query.filter(query, id != ^id)
 end