New Jersey’s largest city is hitting some roadblocks just months after its rising-star mayor went off to Washington. A bold reform plan for the state-run school system has hit a snag, the police department is facing federal oversight over citizen complaints, and the state is threatening a takeover of the city’s finances after several key deadlines were missed. An official who oversees city compliance with state obligations warned the City Council and the interim mayor last month about the state’s growing concern over Newark’s “extraordinary level of fiscal distress.” …