Christopher Vourlias Just moments into the opening sequence of Azra Deniz Okyay’s kinetic drama “Ghosts,” a voice crackles over a radio news bulletin, declaring: “Istanbul has turned into a war zone.” It’s a fittingly turbulent introduction to the writer-director’s feature debut, which charted a rough course to completion en route to winning the Grand Prize at Venice’s Critics’ Week this year.Okyay began writing the script five years ago, struggling to raise financing until a breakthrough last