add confirmation columns

db/migrate/20251125194305_add_confirmable_to_users.rb

@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+class AddConfirmableToUsers < ActiveRecord::Migration[8.0]
+  def change
+    add_column :users, :confirmation_token, :string
+    add_column :users, :confirmed_at, :datetime
+    add_column :users, :confirmation_sent_at, :datetime
+    add_column :users, :unconfirmed_email, :string
+  end
+end