KABUL, Afghanistan (AP) — President Ashraf Ghani has promised a complete overhaul of Afghanistan's government to root out corruption and incompetence, but after three months in office, three missed deadlines and countless promises, he and his election rival-turned-deputy have yet to appoint a single Cabinet minister. The repeated delays have meant that Ghani is single-handedly grappling with a dizzying array of challenges — from a revitalized Taliban insurgency to a reset of long-fraught relations with neighboring Pakistan — and have fueled speculation that he and Chief Executive Abdullah Abdullah, the equivalent of his prime minister, are still at each other's throats. [...] the Taliban remain a potent threat, having carried out a string of high-profile attacks in the capital in recent weeks and caused record casualties among Afghan security forces this year, killing some 5,000 troops and police. Frustration with the snail's pace of progress has fuelled speculation in the local media and among many Afghans that the national unity government formed after a drawn-out and contentious election — through an agreement brokered by U.S.