[
  {
    "type": "add_column",
    "description": "Add payPeriodStart column to stores table for AI schedule rate limiting (Spec 026)",
    "database": "kiosk_buykiosk",
    "check_query": "SHOW COLUMNS FROM `stores` LIKE 'payPeriodStart'",
    "sql": "ALTER TABLE `stores` ADD COLUMN `payPeriodStart` tinyint(1) unsigned DEFAULT NULL COMMENT 'Pay period start day of week (1=Mon, 7=Sun). NULL defaults to Monday.'"
  }
]