fix(ci): 修复剩余的CI错误

- 修复 ops_repo_latency_histogram_buckets.go 中另一个函数的 WriteString 未检查错误
- 修复 ops_repo_request_details.go 和 ops_repo_trends.go 中的 Rows.Close 未检查错误
- 修复 ops_alert_models.go, ops_cleanup_service.go, ops_request_details.go 的格式化问题
- 移除 ops_retry.go 中未使用的 status 字段
- 修复 maxTime 函数重复声明（将测试文件中的函数重命名为 testMaxTime）

backend/internal/service/ops_alert_models.go

@@ -72,4 +72,3 @@ type OpsAlertEventFilter struct {
 	Platform string
 	GroupID  *int64
 }
-

backend/internal/service/ops_cleanup_service.go

@@ -94,19 +94,19 @@ func (s *OpsCleanupService) Start() {
 			if parsed, err := time.LoadLocation(strings.TrimSpace(s.cfg.Timezone)); err == nil && parsed != nil {
 				loc = parsed
 			}
-			}
-	
-			c := cron.New(cron.WithParser(opsCleanupCronParser), cron.WithLocation(loc))
-			_, err := c.AddFunc(schedule, func() { s.runScheduled() })
-			if err != nil {
-				log.Printf("[OpsCleanup] not started (invalid schedule=%q): %v", schedule, err)
-				return
-			}
-			s.cron = c
-			s.cron.Start()
-			log.Printf("[OpsCleanup] started (schedule=%q tz=%s)", schedule, loc.String())
-		})
-	}
+		}
+
+		c := cron.New(cron.WithParser(opsCleanupCronParser), cron.WithLocation(loc))
+		_, err := c.AddFunc(schedule, func() { s.runScheduled() })
+		if err != nil {
+			log.Printf("[OpsCleanup] not started (invalid schedule=%q): %v", schedule, err)
+			return
+		}
+		s.cron = c
+		s.cron.Start()
+		log.Printf("[OpsCleanup] started (schedule=%q tz=%s)", schedule, loc.String())
+	})
+}
 
 func (s *OpsCleanupService) Stop() {
 	if s == nil {

backend/internal/service/ops_request_details.go

@@ -149,4 +149,3 @@ func (s *OpsService) ListRequestDetails(ctx context.Context, filter *OpsRequestD
 		PageSize: pageSize,
 	}, nil
 }
-

backend/internal/service/ops_retry.go

@@ -52,7 +52,6 @@ const (
 type limitedResponseWriter struct {
 	header      http.Header
 	wroteHeader bool
-	status      int
 
 	limit        int
 	totalWritten int64
@@ -65,7 +64,6 @@ func newLimitedResponseWriter(limit int) *limitedResponseWriter {
 	}
 	return &limitedResponseWriter{
 		header: make(http.Header),
-		status: http.StatusOK,
 		limit:  limit,
 	}
 }
@@ -79,7 +77,6 @@ func (w *limitedResponseWriter) WriteHeader(statusCode int) {
 		return
 	}
 	w.wroteHeader = true
-	w.status = statusCode
 }
 
 func (w *limitedResponseWriter) Write(p []byte) (int, error) {