fix: 좀비 슬롯 정리 및 보상 실패 상태 추적

- RequestEntry() 시 CheckStaleSlots() 호출하여 좀비 슬롯 자동 정리
- 블록체인 보상 실패 시 BossRoom 상태를 reward_failed로 업데이트
- UpdateRoomStatus() 레포지토리 메서드 추가

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

internal/bossraid/model.go

@@ -12,7 +12,8 @@ const (
 	StatusWaiting    RoomStatus = "waiting"
 	StatusInProgress RoomStatus = "in_progress"
 	StatusCompleted  RoomStatus = "completed"
-	StatusFailed     RoomStatus = "failed"
+	StatusFailed       RoomStatus = "failed"
+	StatusRewardFailed RoomStatus = "reward_failed"
 )
 
 // BossRoom represents a boss raid session room.

internal/bossraid/repository.go

@@ -219,6 +219,17 @@ func (r *Repository) ResetStaleSlots(threshold time.Time) (int64, error) {
 	return result.RowsAffected, result.Error
 }
 
+// UpdateRoomStatus updates only the status of a boss room by session name.
+func (r *Repository) UpdateRoomStatus(sessionName string, status RoomStatus) error {
+	result := r.db.Model(&BossRoom{}).
+		Where("session_name = ?", sessionName).
+		Update("status", status)
+	if result.RowsAffected == 0 {
+		return fmt.Errorf("방을 찾을 수 없습니다: %s", sessionName)
+	}
+	return result.Error
+}
+
 // GetRoomSlotsByServer returns all room slots for a given server.
 func (r *Repository) GetRoomSlotsByServer(serverID uint) ([]RoomSlot, error) {
 	var slots []RoomSlot

internal/bossraid/service.go

@@ -55,6 +55,9 @@ func (s *Service) SetExpGranter(fn func(username string, exp int) error) {
 // Allocates an idle room slot from a registered dedicated server.
 // Returns the room with assigned session name.
 func (s *Service) RequestEntry(usernames []string, bossID int) (*BossRoom, error) {
+	// 좀비 슬롯 정리 — idle 슬롯 검색 전에 stale 인스턴스를 리셋
+	s.CheckStaleSlots()
+
 	if len(usernames) == 0 {
 		return nil, fmt.Errorf("플레이어 목록이 비어있습니다")
 	}
@@ -222,6 +225,7 @@ func (s *Service) CompleteRaid(sessionName string, rewards []PlayerReward) (*Bos
 
 	// Grant rewards outside the transaction to avoid holding the lock during RPC calls
 	resultRewards = make([]RewardResult, 0, len(rewards))
+	hasRewardFailure := false
 	if s.rewardGrant != nil {
 		for _, r := range rewards {
 			grantErr := s.rewardGrant(r.Username, r.TokenAmount, r.Assets)
@@ -229,11 +233,19 @@ func (s *Service) CompleteRaid(sessionName string, rewards []PlayerReward) (*Bos
 			if grantErr != nil {
 				result.Error = grantErr.Error()
 				log.Printf("보상 지급 실패: %s: %v", r.Username, grantErr)
+				hasRewardFailure = true
 			}
 			resultRewards = append(resultRewards, result)
 		}
 	}
 
+	// 보상 실패가 있으면 상태를 reward_failed로 업데이트
+	if hasRewardFailure {
+		if err := s.repo.UpdateRoomStatus(sessionName, StatusRewardFailed); err != nil {
+			log.Printf("보상 실패 상태 업데이트 실패: %s: %v", sessionName, err)
+		}
+	}
+
 	// Grant experience to players
 	if s.expGrant != nil {
 		for _, r := range rewards {