One rulebreaker who brought a jar of salsa to a public pool in Massachusetts has caused headaches for city officials who say it is costing thousands of dollars to clean up, and for residents who rely on the pool for swim lessons, team practice, fitness and a much-needed break from the heat. The deep pool used for swimming laps at the Rosemary Recreation Complex in Needham, Mass., was closed on Sunday after a jar of salsa shattered, sending shards of glass into the pool, according to an announcement from Needham Park and Recreation. The smaller family pool and splash pad remain open. Massachuse…