Gene Maddaus Senior Media WriterThe membership of the International Alliance of Theatrical Stage Employees has voted to ratify a new three-year agreement, ending the threat of the first national strike in the union’s history.The vote was unusually close, with 256 delegates voting yes on the Basic Agreement, and 188 voting no. On the Area Standards Agreement — which covers 23 locals around the country — the vote was even closer, 103-94.