fix(ci): 修复最后一批CI错误

- 修复 ops_repo_trends.go 中剩余3处 Rows.Close 未检查错误
- 修复 ops_settings.go, ops_settings_models.go, ops_trends.go 的格式化问题

backend/internal/repository/ops_repo_trends.go

@@ -265,7 +265,7 @@ LIMIT $4`
 	if err != nil {
 		return nil, err
 	}
-	defer rows.Close()
+	defer func() { _ = rows.Close() }()
 
 	items := make([]*service.OpsThroughputGroupBreakdownItem, 0, limit)
 	for rows.Next() {
@@ -431,7 +431,7 @@ ORDER BY 1 ASC`
 	if err != nil {
 		return nil, err
 	}
-	defer rows.Close()
+	defer func() { _ = rows.Close() }()
 
 	points := make([]*service.OpsErrorTrendPoint, 0, 256)
 	for rows.Next() {
@@ -542,7 +542,7 @@ LIMIT 20`
 	if err != nil {
 		return nil, err
 	}
-	defer rows.Close()
+	defer func() { _ = rows.Close() }()
 
 	items := make([]*service.OpsErrorDistributionItem, 0, 16)
 	var total int64

backend/internal/service/ops_settings.go

@@ -463,4 +463,3 @@ func (s *OpsService) UpdateOpsAdvancedSettings(ctx context.Context, cfg *OpsAdva
 	_ = json.Unmarshal(raw, updated)
 	return updated, nil
 }
-

backend/internal/service/ops_settings_models.go

@@ -85,4 +85,3 @@ type OpsDataRetentionSettings struct {
 type OpsAggregationSettings struct {
 	AggregationEnabled bool `json:"aggregation_enabled"`
 }
-

backend/internal/service/ops_trends.go

@@ -24,4 +24,3 @@ func (s *OpsService) GetThroughputTrend(ctx context.Context, filter *OpsDashboar
 	}
 	return s.opsRepo.GetThroughputTrend(ctx, filter, bucketSeconds)
 }
-