perfsprint 18→0：strconv.Itoa/FormatInt/FormatUint/FormatBool 替代 fmt.Sprintf、无动词 fmt.Errorf→errors.New、纯字符串拼接。全部语义等价（已核对 diff）。修正 fixer 遗留的 import 问题（引入 goimports 统一整理）。

Result: {"status":"keep","total_issues":56,"golint_canonicalheader":8,"golint_errname":1,"golint_errorlint":12,"golint_forcetypeassert":3,"golint_gosec":0,"golint_intrange":3,"golint_modernize":5,"golint_nilnil":3,"golint_perfsprint":0,"golint_prealloc":3,"golint_recvcheck":7,"golint_usestdlibvars":3,"golint_wastedassign":7,"golint_total":55,"eslint_problems":1,"eslint_errors":0,"eslint_warnings":1,"tsc_errors":0,"measure_s":47}

internal/apps/openflare/flared/logics.go

@@ -28,7 +28,7 @@ const (
 // Heartbeat processes an OpenFlared heartbeat and returns runtime settings.
 func Heartbeat(ctx context.Context, node *model.OpenFlareNode, payload HeartbeatPayload) (*HeartbeatResponse, error) {
 	if node == nil {
-		return nil, fmt.Errorf("tunnel client node is nil")
+		return nil, errors.New("tunnel client node is nil")
 	}
 	if node.NodeType != "tunnel_client" {
 		return nil, fmt.Errorf("node %s is not a tunnel_client", node.NodeID)
@@ -95,7 +95,7 @@ func Heartbeat(ctx context.Context, node *model.OpenFlareNode, payload Heartbeat
 // GetTunnelConfig builds the full tunnel routing config for an OpenFlared client.
 func GetTunnelConfig(ctx context.Context, node *model.OpenFlareNode) (*TunnelConfigResponse, error) {
 	if node == nil {
-		return nil, fmt.Errorf("node is nil")
+		return nil, errors.New("node is nil")
 	}
 
 	activeVersion, err := getActiveConfigMeta(ctx)