Mayor Zohran Mamdani’s uneasy truce with New York’s business elite was tested again Wednesday when he appointed antitrust crusader Lina Khan to a formal post in his administration. Khan will chair the city’s economic development board, which oversees the leasing and use of huge chunks of city property, including Hudson Yards. Semafor first reported, back in November, that Mamdani had tapped Khan as an informal adviser to wield the city’s consumer-protection power. The appointment sends a “mixed message to the business community,” said Steven Fulop, the head of the Partnership for New York City, whose members include Goldman Sachs, Tishman Speyer, Apollo, and Pfizer. A spokesperson for Khan declined to comment, but her camp appears to be enjoying the haters.