SUCCESS: transactions table created/exists!

Table structure:
- id (int)
- user_id (int)
- reservation_id (int)
- book_id (int)
- type (enum('deposit','refund','fine','pending_fine'))
- amount (decimal(10,2))
- status (enum('completed','pending','cancelled'))
- reason (varchar(50))
- days_late (int)
- fine_rate (decimal(10,2))
- notes (text)
- created_at (timestamp)
- processed_at (timestamp)