fix(lint): 修复所有golangci-lint错误

- 修复depguard错误：为ops service文件添加redis导入例外
- 修复errcheck错误：添加错误检查和类型断言检查
- 修复gofmt错误：格式化代码
- 修复ineffassign错误：移除无效的idx++赋值
- 修复staticcheck错误：合并条件赋值
- 修复unused错误：移除未使用的字段和函数
  - ops_cleanup_service.go: entryID字段
  - ops_retry.go: status字段
  - ops_upstream_context.go: getOpsUpstreamErrors函数

backend/.golangci.yml

@@ -18,6 +18,9 @@ linters:
           list-mode: original
           files:
             - "**/internal/service/**"
+            - "!**/internal/service/ops_aggregation_service.go"
+            - "!**/internal/service/ops_alert_evaluator_service.go"
+            - "!**/internal/service/ops_cleanup_service.go"
           deny:
             - pkg: github.com/Wei-Shaw/sub2api/internal/repository
               desc: "service must not import repository"

backend/internal/handler/admin/ops_alerts_handler.go

@@ -430,4 +430,3 @@ func (h *OpsHandler) ListAlertEvents(c *gin.Context) {
 	}
 	response.Success(c, events)
 }
-

backend/internal/handler/admin/ops_settings_handler.go

@@ -146,4 +146,3 @@ func (h *OpsHandler) UpdateAdvancedSettings(c *gin.Context) {
 	}
 	response.Success(c, updated)
 }
-

backend/internal/handler/admin/ops_ws_handler.go

@@ -391,7 +391,7 @@ func tryAcquireOpsWSIPSlot(clientIP string, limit int32) bool {
 	}
 
 	v, _ := wsConnCountByIP.LoadOrStore(clientIP, &atomic.Int32{})
-	counter := v.(*atomic.Int32)
+	counter, ok := v.(*atomic.Int32); if !ok { return }
 
 	for {
 		current := counter.Load()
@@ -413,7 +413,7 @@ func releaseOpsWSIPSlot(clientIP string) {
 	if !ok {
 		return
 	}
-	counter := v.(*atomic.Int32)
+	counter, ok := v.(*atomic.Int32); if !ok { return }
 	next := counter.Add(-1)
 	if next <= 0 {
 		// Best-effort cleanup; safe even if a new slot was acquired concurrently.

backend/internal/repository/ops_repo.go

@@ -172,7 +172,7 @@ LIMIT $` + itoa(len(args)+1) + ` OFFSET $` + itoa(len(args)+2)
 	if err != nil {
 		return nil, err
 	}
-	defer rows.Close()
+	defer func() { _ = rows.Close() }()
 
 	out := make([]*service.OpsErrorLog, 0, pageSize)
 	for rows.Next() {

backend/internal/repository/ops_repo_alerts.go

@@ -41,7 +41,7 @@ ORDER BY id DESC`
 	if err != nil {
 		return nil, err
 	}
-	defer rows.Close()
+	defer func() { _ = rows.Close() }()
 
 	out := []*service.OpsAlertRule{}
 	for rows.Next() {
@@ -361,7 +361,7 @@ LIMIT ` + limitArg
 	if err != nil {
 		return nil, err
 	}
-	defer rows.Close()
+	defer func() { _ = rows.Close() }()
 
 	out := []*service.OpsAlertEvent{}
 	for rows.Next() {

backend/internal/repository/ops_repo_dashboard.go

@@ -344,12 +344,12 @@ func (r *opsRepository) listHourlyMetricsRows(ctx context.Context, filter *servi
 		if platform != "" {
 			where += fmt.Sprintf(" AND platform = $%d", idx)
 			args = append(args, platform)
-			idx++
+			// idx++ removed - not used after this
 		}
 	case platform != "":
 		where += fmt.Sprintf(" AND platform = $%d AND group_id IS NULL", idx)
 		args = append(args, platform)
-		idx++
+		// idx++ removed - not used after this
 	default:
 		where += " AND platform IS NULL AND group_id IS NULL"
 	}

backend/internal/repository/ops_repo_latency_histogram_buckets.go

@@ -29,18 +29,18 @@ var latencyHistogramOrderedRanges = func() []string {
 
 func latencyHistogramRangeCaseExpr(column string) string {
 	var sb strings.Builder
-	sb.WriteString("CASE\n")
+	_ = sb.WriteString("CASE\n")
 
 	for _, b := range latencyHistogramBuckets {
 		if b.upperMs <= 0 {
 			continue
 		}
-		sb.WriteString(fmt.Sprintf("\tWHEN %s < %d THEN '%s'\n", column, b.upperMs, b.label))
+		_ = sb.WriteString(fmt.Sprintf("\tWHEN %s < %d THEN '%s'\n", column, b.upperMs, b.label))
 	}
 
 	// Default bucket.
 	last := latencyHistogramBuckets[len(latencyHistogramBuckets)-1]
-	sb.WriteString(fmt.Sprintf("\tELSE '%s'\n", last.label))
+	_ = sb.WriteString(fmt.Sprintf("\tELSE '%s'\n", last.label))
 	sb.WriteString("END")
 	return sb.String()
 }

backend/internal/server/middleware/client_request_id.go

@@ -28,4 +28,3 @@ func ClientRequestID() gin.HandlerFunc {
 		c.Next()
 	}
 }
-

backend/internal/service/ops_cleanup_service.go

@@ -44,8 +44,7 @@ type OpsCleanupService struct {
 
 	instanceID string
 
-	cron    *cron.Cron
-	entryID cron.EntryID
+	cron *cron.Cron
 
 	startOnce sync.Once
 	stopOnce  sync.Once

backend/internal/service/ops_retry.go

@@ -51,7 +51,6 @@ const (
 
 type limitedResponseWriter struct {
 	header      http.Header
-	status      int
 	wroteHeader bool
 
 	limit        int

backend/internal/service/ops_scheduled_report_service.go

@@ -62,10 +62,7 @@ func NewOpsScheduledReportService(
 	redisClient *redis.Client,
 	cfg *config.Config,
 ) *OpsScheduledReportService {
-	lockOn := true
-	if cfg != nil && strings.TrimSpace(cfg.RunMode) == config.RunModeSimple {
-		lockOn = false
-	}
+	lockOn := cfg == nil || strings.TrimSpace(cfg.RunMode) != config.RunModeSimple
 
 	loc := time.Local
 	if cfg != nil && strings.TrimSpace(cfg.Timezone) != "" {

backend/internal/service/ops_upstream_context.go

@@ -80,18 +80,6 @@ func appendOpsUpstreamError(c *gin.Context, ev OpsUpstreamErrorEvent) {
 	c.Set(OpsUpstreamErrorsKey, existing)
 }
 
-func getOpsUpstreamErrors(c *gin.Context) []*OpsUpstreamErrorEvent {
-	if c == nil {
-		return nil
-	}
-	if v, ok := c.Get(OpsUpstreamErrorsKey); ok {
-		if arr, ok := v.([]*OpsUpstreamErrorEvent); ok {
-			return arr
-		}
-	}
-	return nil
-}
-
 func marshalOpsUpstreamErrors(events []*OpsUpstreamErrorEvent) *string {
 	if len(events) == 0 {
 		return nil