fix: restore battle entry and character profile initialization

internal/gameserver/handlers_challenge_scene.go

@@ -167,6 +167,7 @@ func loadChallengeScene(s *Session, entryID, targetGroupID, monsterID, eventID u
 	// single boss monster (entity 30001, registered for SceneCastSkill battles)
 	monsterGroup := &goproto.SceneEntityGroupInfo{GroupId: targetGroupID}
 	s.MonsterEntities = map[uint32]uint32{30001: eventID}
+	s.ChallengeStageID = eventID
 	monsterGroup.EntityList = append(monsterGroup.EntityList, &goproto.SceneEntityInfo{
 		InstId:   instID,
 		GroupId:  targetGroupID,