```release-note:enhancement resource/aws_cognito_user_pool: Add `custom_domain`, `domain`, and `estimated_number_of_users` attributes ``` ```release-note:enhancement resource/aws_cognito_user_pool: Add plan time validation for `name` ``` ```release-note:enhancement resource/aws_cognito_user_pool: Add `custom_email_sender`, `custom_sms_sender`, and `kms_key_id` to `lambda_config` ```