As the nation’s largest bank continues to deal with sluggish revenue, J.P. Morgan Chase & Co. is sharpening its cost-cutting knife on everything from real estate to its choice of armored trucks. In the past few months, the bank’s chief operating officer, Matt Zames, has redoubled the firm’s focus on cost cutting to include relocating employees to less expensive office space, revising third-party contracts and re-examining relationships with market-data providers, among others, people familiar with the matter said. The push by Mr.