KANSAS CITY, Mo. — Sunday’s first half provided a game of firsts for a trio of Chiefs players. Wide receiver Kadarius Toney scored his first career touchdown; wide receiver Marquez Valdes-Scantling notched his first touchdown in a Chiefs uniform; and tight end Noah Gray recorded his first touchdown of the season. The Chiefs rode the strength of those three first-half scores en route to a 27-17 win over the Jacksonville Jaguars at GEHA Field at Arrowhead Stadium. Toney got it started early with a 6-yard touchdown and showed some athleticism on his way to the end zone. Quarterback Patrick Mahome…