For months, one question has plagued moviegoers: “who is the real Agent Argylle?” It’s a query posed by Samuel L. Jackson in the ubiquitous trailer for Matthew Vaughn’s spy action-comedy “Argylle,” though there are more pressing questions that the trailer presents, like, “who thought a flat-top on Henry Cavill was a good idea?” and, “why are we spelling argyle with two Ls?” Alas, those latter questions remain a mystery, but the film does take up the former, delving into the convoluted identity of the real Agent Argylle for an absolutely unbearable 2 hours and 19 minutes. It’s remarkable really…