Iran’s top diplomat warned Sunday that any attempt by ships to bypass its preferred route through the Strait of Hormuz would “increase tensions” in the Middle East, as US and Iranian forces again traded attacks. The exchanges underscored the fragility of a Pakistan-brokered agreement aimed at ending the war launched by the United States and Israel in February that disrupted shipping through the strait and rattled global energy markets. Although a ceasefire took effect in April, sporadic violence...