=== 라운드 ID 마이그레이션 시작 ===

- game_rounds.round_id 컬럼 이미 존재
- round_id 인덱스 이미 존재
- bet_attempts.round_id_str 컬럼 이미 존재
- round_participants.round_id_str 컬럼 이미 존재
- bet_logs.round_id_str 컬럼 이미 존재
- round_summary.round_id 컬럼 이미 존재
✓ 빈 라운드 1개 삭제됨

=== 마이그레이션 완료 ===

현재 game_rounds 테이블 구조:
  - id: int(11)
  - round_id: varchar(12)
  - round_number: int(11)
  - btc_round_id: int(11)
  - status: enum('waiting','betting','locked','settled')
  - start_price: decimal(20,8)
  - end_price: decimal(20,8)
  - result: enum('UP','DOWN','DRAW')
  - price_change: decimal(10,4)
  - total_up_bet: decimal(15,2)
  - total_down_bet: decimal(15,2)
  - requested_up_bet: decimal(15,2)
  - requested_down_bet: decimal(15,2)
  - approved_up_bet: decimal(15,2)
  - approved_down_bet: decimal(15,2)
  - up_participants: int(11)
  - down_participants: int(11)
  - matched_amount: decimal(15,2)
  - up_return_amount: decimal(15,2)
  - down_return_amount: decimal(15,2)
  - up_return_percent: decimal(5,2)
  - down_return_percent: decimal(5,2)
  - fee_percent: decimal(5,2)
  - payout_rate: decimal(6,4)
  - total_payout: decimal(15,2)
  - house_profit: decimal(15,2)
  - betting_start_at: timestamp
  - betting_end_at: timestamp
  - settled_at: timestamp
  - created_at: timestamp
  - void_reason: varchar(255)