Allow redeem codes with negative values to enable refund scenarios:
- Balance: negative value deducts balance (clamped to 0, never negative)
- Concurrency: negative value reduces concurrency (clamped to 0)
- Subscription: negative validity_days reduces remaining days; if
remaining days <= 0, the subscription is canceled (set to expired)
All deductions generate standard redeem code records for audit trail.
- Add new API endpoint GET /admin/users/:id/balance-history with pagination and type filter
- Add SumPositiveBalanceByUser for calculating total recharged amount
- Create UserBalanceHistoryModal component with:
- User info header (email, username, created_at, current balance, notes, total recharged)
- Type filter dropdown (all/balance/admin_balance/concurrency/admin_concurrency/subscription)
- Quick deposit/withdraw buttons
- Paginated history list with icons and colored values
- Add instant tooltip on balance column for better UX
- Add z-index prop to BaseDialog for modal stacking control
- Update i18n translations (zh/en)
