CREATE TABLE IF NOT EXISTS licenses (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  license_key VARCHAR(64) NOT NULL,
  status ENUM('active','revoked') NOT NULL DEFAULT 'active',
  expires_at DATETIME NOT NULL,
  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  PRIMARY KEY (id),
  UNIQUE KEY uq_license_key (license_key),
  KEY idx_status_expiry (status, expires_at)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;