feat(admin): add user balance/concurrency history modal

- 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)

backend/internal/handler/admin/user_handler.go

@@ -277,3 +277,44 @@ func (h *UserHandler) GetUserUsage(c *gin.Context) {
 
 	response.Success(c, stats)
 }
+
+// GetBalanceHistory handles getting user's balance/concurrency change history
+// GET /api/v1/admin/users/:id/balance-history
+// Query params:
+//   - type: filter by record type (balance, admin_balance, concurrency, admin_concurrency, subscription)
+func (h *UserHandler) GetBalanceHistory(c *gin.Context) {
+	userID, err := strconv.ParseInt(c.Param("id"), 10, 64)
+	if err != nil {
+		response.BadRequest(c, "Invalid user ID")
+		return
+	}
+
+	page, pageSize := response.ParsePagination(c)
+	codeType := c.Query("type")
+
+	codes, total, totalRecharged, err := h.adminService.GetUserBalanceHistory(c.Request.Context(), userID, page, pageSize, codeType)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+
+	// Convert to admin DTO (includes notes field for admin visibility)
+	out := make([]dto.AdminRedeemCode, 0, len(codes))
+	for i := range codes {
+		out = append(out, *dto.RedeemCodeFromServiceAdmin(&codes[i]))
+	}
+
+	// Custom response with total_recharged alongside pagination
+	pages := int((total + int64(pageSize) - 1) / int64(pageSize))
+	if pages < 1 {
+		pages = 1
+	}
+	response.Success(c, gin.H{
+		"items":           out,
+		"total":           total,
+		"page":            page,
+		"page_size":       pageSize,
+		"pages":           pages,
+		"total_recharged": totalRecharged,
+	})
+}

backend/internal/repository/redeem_code_repo.go

@@ -202,6 +202,57 @@ func (r *redeemCodeRepository) ListByUser(ctx context.Context, userID int64, lim
 	return redeemCodeEntitiesToService(codes), nil
 }
 
+// ListByUserPaginated returns paginated balance/concurrency history for a user.
+// Supports optional type filter (e.g. "balance", "admin_balance", "concurrency", "admin_concurrency", "subscription").
+func (r *redeemCodeRepository) ListByUserPaginated(ctx context.Context, userID int64, params pagination.PaginationParams, codeType string) ([]service.RedeemCode, *pagination.PaginationResult, error) {
+	q := r.client.RedeemCode.Query().
+		Where(redeemcode.UsedByEQ(userID))
+
+	// Optional type filter
+	if codeType != "" {
+		q = q.Where(redeemcode.TypeEQ(codeType))
+	}
+
+	total, err := q.Count(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	codes, err := q.
+		WithGroup().
+		Offset(params.Offset()).
+		Limit(params.Limit()).
+		Order(dbent.Desc(redeemcode.FieldUsedAt)).
+		All(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return redeemCodeEntitiesToService(codes), paginationResultFromTotal(int64(total), params), nil
+}
+
+// SumPositiveBalanceByUser returns total recharged amount (sum of value > 0 where type is balance/admin_balance).
+func (r *redeemCodeRepository) SumPositiveBalanceByUser(ctx context.Context, userID int64) (float64, error) {
+	var result []struct {
+		Sum float64 `json:"sum"`
+	}
+	err := r.client.RedeemCode.Query().
+		Where(
+			redeemcode.UsedByEQ(userID),
+			redeemcode.ValueGT(0),
+			redeemcode.TypeIn("balance", "admin_balance"),
+		).
+		Aggregate(dbent.As(dbent.Sum(redeemcode.FieldValue), "sum")).
+		Scan(ctx, &result)
+	if err != nil {
+		return 0, err
+	}
+	if len(result) == 0 {
+		return 0, nil
+	}
+	return result[0].Sum, nil
+}
+
 func redeemCodeEntityToService(m *dbent.RedeemCode) *service.RedeemCode {
 	if m == nil {
 		return nil

backend/internal/server/routes/admin.go

@@ -172,6 +172,7 @@ func registerUserManagementRoutes(admin *gin.RouterGroup, h *handler.Handlers) {
 		users.POST("/:id/balance", h.Admin.User.UpdateBalance)
 		users.GET("/:id/api-keys", h.Admin.User.GetUserAPIKeys)
 		users.GET("/:id/usage", h.Admin.User.GetUserUsage)
+		users.GET("/:id/balance-history", h.Admin.User.GetBalanceHistory)
 
 		// User attribute values
 		users.GET("/:id/attributes", h.Admin.UserAttribute.GetUserAttributes)

backend/internal/service/admin_service.go

@@ -22,6 +22,10 @@ type AdminService interface {
 	UpdateUserBalance(ctx context.Context, userID int64, balance float64, operation string, notes string) (*User, error)
 	GetUserAPIKeys(ctx context.Context, userID int64, page, pageSize int) ([]APIKey, int64, error)
 	GetUserUsageStats(ctx context.Context, userID int64, period string) (any, error)
+	// GetUserBalanceHistory returns paginated balance/concurrency change records for a user.
+	// codeType is optional - pass empty string to return all types.
+	// Also returns totalRecharged (sum of all positive balance top-ups).
+	GetUserBalanceHistory(ctx context.Context, userID int64, page, pageSize int, codeType string) ([]RedeemCode, int64, float64, error)
 
 	// Group management
 	ListGroups(ctx context.Context, page, pageSize int, platform, status, search string, isExclusive *bool) ([]Group, int64, error)
@@ -522,6 +526,21 @@ func (s *adminServiceImpl) GetUserUsageStats(ctx context.Context, userID int64,
 	}, nil
 }
 
+// GetUserBalanceHistory returns paginated balance/concurrency change records for a user.
+func (s *adminServiceImpl) GetUserBalanceHistory(ctx context.Context, userID int64, page, pageSize int, codeType string) ([]RedeemCode, int64, float64, error) {
+	params := pagination.PaginationParams{Page: page, PageSize: pageSize}
+	codes, result, err := s.redeemCodeRepo.ListByUserPaginated(ctx, userID, params, codeType)
+	if err != nil {
+		return nil, 0, 0, err
+	}
+	// Aggregate total recharged amount (only once, regardless of type filter)
+	totalRecharged, err := s.redeemCodeRepo.SumPositiveBalanceByUser(ctx, userID)
+	if err != nil {
+		return nil, 0, 0, err
+	}
+	return codes, result.Total, totalRecharged, nil
+}
+
 // Group management implementations
 func (s *adminServiceImpl) ListGroups(ctx context.Context, page, pageSize int, platform, status, search string, isExclusive *bool) ([]Group, int64, error) {
 	params := pagination.PaginationParams{Page: page, PageSize: pageSize}

backend/internal/service/redeem_service.go

@@ -49,6 +49,11 @@ type RedeemCodeRepository interface {
 	List(ctx context.Context, params pagination.PaginationParams) ([]RedeemCode, *pagination.PaginationResult, error)
 	ListWithFilters(ctx context.Context, params pagination.PaginationParams, codeType, status, search string) ([]RedeemCode, *pagination.PaginationResult, error)
 	ListByUser(ctx context.Context, userID int64, limit int) ([]RedeemCode, error)
+	// ListByUserPaginated returns paginated balance/concurrency history for a specific user.
+	// codeType filter is optional - pass empty string to return all types.
+	ListByUserPaginated(ctx context.Context, userID int64, params pagination.PaginationParams, codeType string) ([]RedeemCode, *pagination.PaginationResult, error)
+	// SumPositiveBalanceByUser returns the total recharged amount (sum of positive balance values) for a user.
+	SumPositiveBalanceByUser(ctx context.Context, userID int64) (float64, error)
 }
 
 // GenerateCodesRequest 生成兑换码请求