BOSTON (AP) — The Boston Symphony Orchestra and its musicians have decided to extend their collective bargaining agreement for 48 hours, a sign they could be nearing a deal to head off what would have been the first strike in the ensemble’s 145-year history. The Boston Musicians’ Association said Saturday it had authorized a strike ahead of the expiration of the union’s three-year contract at 11:59 p. m. Sunday. The BSO and the musicians said Sunday the contract had been extended to p...