Sync user email to member when changing password (admin_set_password)

Add SyncUserEmailToMember change to admin_set_password so email+password
updates in the user form sync the new email to the linked member.

test/accounts/user_email_sync_test.exs

@@ -120,6 +120,43 @@ defmodule Mv.Accounts.UserEmailSyncTest do
       {:ok, member_after_unlink} = Ash.get(Mv.Membership.Member, member.id, actor: actor)
       assert member_after_unlink.email == "user@example.com"
     end
+
+    test "admin_set_password with email change syncs to linked member", %{actor: actor} do
+      # Create member and user linked to it (with password so admin_set_password applies)
+      {:ok, member} = Membership.create_member(@valid_member_attrs, actor: actor)
+
+      {:ok, user} =
+        Mv.Accounts.User
+        |> Ash.Changeset.for_create(:register_with_password, %{
+          email: "user@example.com",
+          password: "initialpass123"
+        })
+        |> Ash.create(actor: actor)
+
+      {:ok, user} =
+        user
+        |> Ash.Changeset.for_update(:update_user, %{member: %{id: member.id}})
+        |> Ash.update(actor: actor)
+
+      assert user.member_id == member.id
+      {:ok, m} = Ash.get(Mv.Membership.Member, member.id, actor: actor)
+      assert m.email == "user@example.com"
+
+      # Change both email and password via admin_set_password (e.g. user form "Change Password")
+      {:ok, updated_user} =
+        user
+        |> Ash.Changeset.for_update(:admin_set_password, %{
+          email: "newemail@example.com",
+          password: "newpassword123"
+        })
+        |> Ash.update(actor: actor)
+
+      assert to_string(updated_user.email) == "newemail@example.com"
+
+      # Member email must be synced (Option A: SyncUserEmailToMember on admin_set_password)
+      {:ok, synced_member} = Ash.get(Mv.Membership.Member, member.id, actor: actor)
+      assert synced_member.email == "newemail@example.com"
+    end
   end
 
   describe "AshAuthentication compatibility" do