Well-heeled New Yorkers working in one Manhattan skyscraper will soon be able to get plastic surgery, liposuction, cat scans and other medical treatments at the push of an elevator button. At 9 W. 57th St. — which houses Chanel, asset manager Apollo Global Management, and private-equity firm Veritas Capital — the landlord is building a luxury medical center on the 24th floor along with a tenant-only amenity floor with a restaurant and bar, as well as a basement-level health center. “Almost all modern-day buildings have health clubs,” said Michael Hershman, CEO of the Soloviev Group, owner of t…