The Usher-headlined Apple Music Super Bowl LVIII Halftime Show featured plenty of guest stars at Allegiant Allegiant Stadium in Las Vegas on Sunday. But it didn’t feature the one that millions of viewers were hoping to see during during the break in action between the San Francisco 49ers and the Kansas City Chiefs. Nope. Taylor Swift — who was at the game to support boyfriend Travis Kelce of the Chiefs — did not join Usher onstage. Instead, viewers got to see guest appearances from Alicia Keys, Will.i.am, Ludacris, Lil Jon and, best of all, the Bay Area’s own H.E.R. during the approximately 13…