fix(channelserver): handle silently swallowed DB scan and exec errors

Several handlers discarded errors from rows.Scan() and db.Exec(),
masking data corruption or connection issues. Scan failures in diva
schedule, event quests, and trend weapons are now logged or returned.
InitializeWarehouse now surfaces its insert error to the caller.

server/channelserver/handlers_diva.go

@@ -84,7 +84,9 @@ func handleMsgMhfGetUdSchedule(s *Session, p mhfpacket.MHFPacket) {
 	} else {
 		defer func() { _ = rows.Close() }()
 		for rows.Next() {
-			_ = rows.Scan(&id, &start)
+			if err := rows.Scan(&id, &start); err != nil {
+				s.logger.Error("Failed to scan diva schedule row", zap.Error(err))
+			}
 		}
 	}
 

server/channelserver/handlers_house.go

@@ -330,7 +330,9 @@ func handleMsgMhfAcquireTitle(s *Session, p mhfpacket.MHFPacket) {
 func handleMsgMhfResetTitle(s *Session, p mhfpacket.MHFPacket) {}
 
 func initializeWarehouse(s *Session) {
-	s.server.houseRepo.InitializeWarehouse(s.charID)
+	if err := s.server.houseRepo.InitializeWarehouse(s.charID); err != nil {
+		s.logger.Error("Failed to initialize warehouse", zap.Error(err), zap.Uint32("charID", s.charID))
+	}
 }
 
 func handleMsgMhfOperateWarehouse(s *Session, p mhfpacket.MHFPacket) {

server/channelserver/handlers_house_test.go

@@ -529,7 +529,7 @@ func TestOperateWarehouse_Op0_GetBoxNames(t *testing.T) {
 	_, _, session, charID := setupHouseTest(t)
 
 	// Initialize warehouse and rename a box
-	session.server.houseRepo.InitializeWarehouse(charID)
+	_ = session.server.houseRepo.InitializeWarehouse(charID)
 	_ = session.server.houseRepo.RenameWarehouseBox(charID, 0, 0, "MyItems")
 
 	pkt := &mhfpacket.MsgMhfOperateWarehouse{

server/channelserver/handlers_misc.go

@@ -261,7 +261,10 @@ func handleMsgMhfGetTrendWeapon(s *Session, p mhfpacket.MHFPacket) {
 		j := 0
 		for rows.Next() {
 			trendWeapons[i][j].WeaponType = i
-			_ = rows.Scan(&trendWeapons[i][j].WeaponID)
+			if err := rows.Scan(&trendWeapons[i][j].WeaponID); err != nil {
+				s.logger.Error("Failed to scan trend weapon", zap.Error(err))
+				break
+			}
 			j++
 		}
 	}

server/channelserver/handlers_quest.go

@@ -269,7 +269,9 @@ func makeEventQuest(s *Session, rows *sql.Rows) ([]byte, error) {
 	var questId, activeDuration, inactiveDuration, flags int
 	var maxPlayers, questType uint8
 	var startTime time.Time
-	_ = rows.Scan(&id, &maxPlayers, &questType, &questId, &mark, &flags, &startTime, &activeDuration, &inactiveDuration)
+	if err := rows.Scan(&id, &maxPlayers, &questType, &questId, &mark, &flags, &startTime, &activeDuration, &inactiveDuration); err != nil {
+		return nil, fmt.Errorf("failed to scan event quest row: %w", err)
+	}
 
 	data := loadQuestFile(s, questId)
 	if data == nil {

server/channelserver/repo_house.go

@@ -97,12 +97,14 @@ func (r *HouseRepository) UpdateMission(charID uint32, data []byte) error {
 // Warehouse methods
 
 // InitializeWarehouse ensures a warehouse row exists for the character.
-func (r *HouseRepository) InitializeWarehouse(charID uint32) {
+func (r *HouseRepository) InitializeWarehouse(charID uint32) error {
 	var t int
 	err := r.db.QueryRow(`SELECT character_id FROM warehouse WHERE character_id=$1`, charID).Scan(&t)
 	if err != nil {
-		_, _ = r.db.Exec(`INSERT INTO warehouse (character_id) VALUES ($1)`, charID)
+		_, err = r.db.Exec(`INSERT INTO warehouse (character_id) VALUES ($1)`, charID)
+		return err
 	}
+	return nil
 }
 
 const warehouseNamesSQL = `