分销后台前端对接与结算明细接口

- 新增 GET /admin/distribution/settlement-batches/:id/items 明细查询
- distribution-admin 重构为 react-router 多页面：仪表盘/网站/规则(启停)/订单(筛选分页)/结算(创建/明细/结算)/支付通道(绑定解绑)/账号展示(上下架)
- axios 统一 401 提示，引导回主站后台登录；金额统一整数分格式化
- npm run build(tsc 严格模式) 通过

backend/internal/modules/distribution/repository.go

@@ -582,3 +582,33 @@ func (r *Repository) CreateFinancialSnapshot(ctx context.Context, adminID, order
 	}
 	return r.FindOrder(ctx, adminID, orderID)
 }
+
+func (r *Repository) ListSettlementItems(ctx context.Context, adminID, batchID uint64) ([]SettlementItemDTO, error) {
+	var batch model.DistributionSettlementBatch
+	if err := r.db.WithContext(ctx).First(&batch, batchID).Error; err != nil {
+		if errors.Is(err, gorm.ErrRecordNotFound) {
+			return nil, ErrSettlementBatchNotFound
+		}
+		return nil, err
+	}
+	if err := r.ensureSiteAccess(ctx, adminID, batch.SiteID); err != nil {
+		return nil, err
+	}
+	var rows []struct {
+		model.DistributionSettlementItem
+		PartyRole string
+	}
+	if err := r.db.WithContext(ctx).
+		Table("distribution_settlement_items i").
+		Select("i.id, i.order_id, i.amount_cent, i.status, p.party_role").
+		Joins("JOIN distribution_order_parties p ON p.id = i.party_id").
+		Where("i.batch_id = ?", batchID).
+		Order("i.id ASC").Scan(&rows).Error; err != nil {
+		return nil, err
+	}
+	items := make([]SettlementItemDTO, 0, len(rows))
+	for _, row := range rows {
+		items = append(items, SettlementItemDTO{ID: row.ID, OrderID: row.OrderID, PartyRole: row.PartyRole, AmountCent: row.AmountCent, Status: row.Status})
+	}
+	return items, nil
+}