Print Marvel movie fans are old pros at understanding the concept of a multiverse, where different versions of the Avengers superheroes are living parallel lives in alternate timelines. That’s the same concept behind Nick Payne’s touching 2012 play “Constellations,” where the lives and relationship of romantically intertwined characters Marianne and Roland twist, turn, merge and diverge in dozens of ways during the 70-minute, shape-shifting play. San Diegans got their first look at the bittersweet comedy-drama five years ago in a haunting and moving production at the Old Globe. It’s back this month in a filmed production by Coronado Playhouse that’s available for on-demand streaming through May 30.