feat: License 支持筛选多选批量删除

仅已吊销或已过期可删，有效授权自动跳过；单条删除同步限制。

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/internal/service/license/license_service.go

@@ -161,18 +161,72 @@ func (s *LicenseService) Update(id uint, updates map[string]interface{}) (*dto.L
 	return &resp, nil
 }
 
-// Delete 删除 License（软删除） // Logan.Li
+// Delete 删除 License（仅允许已吊销或已过期；软删除） // Logan.Li
 func (s *LicenseService) Delete(id uint) (*model.License, error) {
 	var lic model.License
 	if err := s.db.First(&lic, id).Error; err != nil {
 		return nil, errors.New("License 不存在")
 	}
+	if !isDeletableLicense(lic) {
+		return nil, errors.New("仅已吊销或已过期的 License 可删除")
+	}
 	if err := s.db.Delete(&model.License{}, id).Error; err != nil {
 		return nil, errors.New("删除 License 失败")
 	}
 	return &lic, nil
 }
 
+// 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：仅删已吊销/已过期，其余跳过 // Logan.Li
+func (s *LicenseService) BatchDelete(ids []uint) (*BatchDeleteResult, error) {
+	result := &BatchDeleteResult{}
+	if len(ids) == 0 {
+		return result, nil
+	}
+	seen := map[uint]struct{}{}
+	for _, id := range ids {
+		if id == 0 {
+			continue
+		}
+		if _, ok := seen[id]; ok {
+			continue
+		}
+		seen[id] = struct{}{}
+
+		var lic model.License
+		if err := s.db.First(&lic, id).Error; err != nil {
+			result.Failed++
+			continue
+		}
+		if !isDeletableLicense(lic) {
+			result.Skipped++
+			result.SkippedIDs = append(result.SkippedIDs, id)
+			continue
+		}
+		if err := s.db.Delete(&model.License{}, id).Error; err != nil {
+			result.Failed++
+			continue
+		}
+		result.Deleted++
+	}
+	return result, nil
+}
+
+// isDeletableLicense 仅吊销或到期可物理清理（软删） // Logan.Li
+func isDeletableLicense(lic model.License) bool {
+	if lic.Status == model.LicenseStatusRevoked || lic.Status == model.LicenseStatusExpired {
+		return true
+	}
+	return utils.IsLicenseExpired(lic.EndDate)
+}
+
 // Renew 续期（仅在线证；离线证签名自包含，到期后应重新签发） // Logan.Li
 func (s *LicenseService) Renew(id uint, duration int) (*dto.LicenseResponse, error) {
 	var lic model.License