Iran’s top diplomat, an architect of the landmark nuclear deal, resigned on Monday, hobbling the relatively moderate government of President Hassan Rouhani and its chances of keeping the pact alive. Foreign Minister Javad Zarif’s unexpected resignation, announced on his Instagram account late at night in Iran, signals a victory for Iran’s hard-liners, who favor confrontation with the West, as Washington ratchets up pressure on the country after pulling out of the deal. …