The seats tell the story.At Citi Field this week, large sections of the ballpark sat noticeably empty during a midweek game — a stark visual for a franchise that entered the season with expectations far higher than what’s played out so far.For the New York Mets, the drop in attendance isn’t happening in a vacuum. It’s being reflected directly in the secondary ticket market, where prices have quietly dipped to levels rarely seen for a team in New…