Sean “Diddy” Combs was once viewed as a “modern-day Gatsby” whose extravagant A-list parties were hailed as legendary. But these get-togethers emerged in a new light after the hip hop producer was slapped with a federal sex trafficking indictment detailing the depraved “freak-offs” he’s been accused of orchestrating. RadarOnline.com obtained photos from one of Diddy’s star-studded soirees, showing the likes of Leonardo Dicaprio, Chevy Chase and Regis Philbin schmoozing at his swanky beachfront mansion in the Hamptons in 1999. A photojournalist also claimed to have spotted Diddy and his ex, Jen…