PARIS — Paris Fashion Week officially ended with Louis Vuitton on Tuesday night, but a couple of hours later, Anthony Vaccarello delivered his own envoi in the form of a men’s collection for Saint Laurent. Shrouded in secrecy until the last minute, it played to an audience of barely a hundred (compared to Vuitton’s thousands) in the cavernous rotunda of the Bourse de Commerce, the Paris home of the Pinault Foundation. It was carpeted…