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/helpers.ex

@@ -5,6 +5,8 @@ defmodule Mv.Helpers do
   Provides utilities that are not specific to a single domain or layer.
   """
 
+  require Ash.Query
+
   @doc """
   Converts an actor to Ash options list for authorization.
   Returns empty list if actor is nil.
@@ -24,4 +26,22 @@ defmodule Mv.Helpers do
   @spec ash_actor_opts(Mv.Accounts.User.t() | nil) :: keyword()
   def ash_actor_opts(nil), do: []
   def ash_actor_opts(actor) when not is_nil(actor), do: [actor: actor]
+
+  @doc """
+  Returns the query unchanged if `exclude_id` is nil; otherwise adds a filter `id != ^exclude_id`.
+
+  Used in uniqueness validations that must exclude the current record (e.g. name uniqueness
+  on update, duplicate association checks). Call with the record's primary key to exclude it
+  from the result set.
+
+  ## Examples
+
+      query
+      |> Ash.Query.filter(name == ^name)
+      |> Mv.Helpers.query_exclude_id(current_id)
+
+  """
+  @spec query_exclude_id(Ash.Query.t(), String.t() | nil) :: Ash.Query.t()
+  def query_exclude_id(query, nil), do: query
+  def query_exclude_id(query, id), do: Ash.Query.filter(query, id != ^id)
 end