Attorney General Martha Coakley has reached a deal with Steward Health Care System that requires the for-profit hospital operator to keep a temporary emergency room at Quincy Medical Center and other services in Quincy. The settlement does not penalize Steward for shuttering its Quincy hospital last month, even though that closure was in violation of a 2011 contract with Coakley's office. Steward kept the emergency room at Quincy Medical Center open even after ending other hospital services the day after Christmas. Coakley said Wednesday that Steward must maintain the emergency room until the end of 2015, or face up to $30,000 a month in fines.