Like many 21st-century relationships, ​CARPOOL TUNNEL ​started with the swipe of an app. Just two weeks after an ad for Vampr – hailed as Tinder for musicians – came across Daniel Stauffer’s phone in 2017, the Bay Area drummer was in the studio along with two fellow Vampr users, guitarist Bradley Kearsley and singer/guitarist Ben Koppenjan, recording their debut single “Afterlight” with Grammy-nominated producer Billy Mohler. One new member – bassist Spencer Layne – and a $…