My [Repair] Skill Became a Versatile Cheat, So I Think I’ll Open a Weapon Shop (Light Novel)

Luke was in the middle of conquering a high-difficulty dungeon when he was abandoned by the Hero. In his quest for survival, his “Repair” skill evolved, allowing him to somehow escape the dungeon! Disillusioned with adventuring, he thought of opening a weapons shop to make a living but it became unexpectedly popular—?