feat: 产品/客户/订单批量删除；接入 GeoLite2 城市库（地理分布/激活记录/审计日志显示归属地）；仪表盘趋势图美化

backend/internal/service/customer/batch.go

@@ -0,0 +1,41 @@
+package customer
+
+import "backend/internal/model"
+
+// BatchDeleteResult 批量删除结果 // Logan.Li
+type BatchDeleteResult struct {
+	Deleted    int    `json:"deleted"`
+	Skipped    int    `json:"skipped"`
+	Failed     int    `json:"failed"`
+	SkippedIDs []uint `json:"skipped_ids,omitempty"`
+}
+
+// BatchDelete 批量删除客户：名下有 License 的跳过；其余软删除并清理产品关联 // Logan.Li
+func (s *CustomerService) BatchDelete(ids []uint) (*BatchDeleteResult, error) {
+	result := &BatchDeleteResult{}
+	seen := map[uint]struct{}{}
+	for _, id := range ids {
+		if id == 0 {
+			continue
+		}
+		if _, ok := seen[id]; ok {
+			continue
+		}
+		seen[id] = struct{}{}
+
+		var licCount int64
+		s.db.Model(&model.License{}).Where("customer_id = ?", id).Count(&licCount)
+		if licCount > 0 {
+			result.Skipped++
+			result.SkippedIDs = append(result.SkippedIDs, id)
+			continue
+		}
+		if err := s.db.Delete(&model.Customer{}, id).Error; err != nil {
+			result.Failed++
+			continue
+		}
+		s.db.Where("customer_id = ?", id).Delete(&model.CustomerProduct{})
+		result.Deleted++
+	}
+	return result, nil
+}