CW Riverdale (CW, 9:00pm) — Sabrina Spellman’s due on the scene soon, all while Veronica and Reggie have become a power couple, and Jughead moves in with Tabatha. The Archiverse is about to grow even stranger than it’s been already, and thank goodness the “war” is over. The Flash (CW, 8:00pm) — Team Flash must …