A Kevin Durant trade to the Phoenix Suns just became much more difficult, if not impossible. Suns restricted free agent center Deandre Ayton is expected to sign the largest offer sheet in NBA history — a four-year, $133 million deal with the Indiana Pacers — that the Suns will have 48 hours to decide whether or not to match. Ayton, who has been on the outs in Phoenix ever since they opted against extending his contract last summer, has been an integral piece to any hypothetical Durant deal between the Nets and the Suns. And as soon as he puts pen to paper with an offer sheet, Ayton is official…