Revert "[connector/datadog] Remove feature gate connector.datadogconnector.performance" (open-telemetry#31639)

Reverts open-telemetry#31638

Author: songy23

.chloggen/dd-feature-gate-removal.yaml

@@ -19,6 +19,7 @@ import (
 	"github.com/DataDog/datadog-agent/pkg/trace/timing"
 	"github.com/DataDog/datadog-go/v5/statsd"
 	"github.com/DataDog/opentelemetry-mapping-go/pkg/otlp/metrics"
+	"go.opentelemetry.io/collector/featuregate"
 	"go.opentelemetry.io/collector/pdata/ptrace"
 )
 
@@ -37,6 +38,13 @@ type TraceAgent struct {
 	exit chan struct{}
 }
 
+var _ = featuregate.GlobalRegistry().MustRegister(
+	"connector.datadogconnector.performance",
+	featuregate.StageStable,
+	featuregate.WithRegisterDescription("Datadog Connector will use optimized code"),
+	featuregate.WithRegisterToVersion("0.97.0"),
+)
+
 // newAgent creates a new unstarted traceagent using the given context. Call Start to start the traceagent.
 // The out channel will receive outoing stats payloads resulting from spans ingested using the Ingest method.
 func NewAgent(ctx context.Context, out chan *pb.StatsPayload, metricsClient statsd.ClientInterface, timingReporter timing.Reporter) *TraceAgent {

internal/datadog/agent.go

@@ -10,6 +10,7 @@ require (
 	github.com/DataDog/opentelemetry-mapping-go/pkg/otlp/metrics v0.13.4
 	github.com/stretchr/testify v1.9.0
 	go.opentelemetry.io/collector/component v0.96.1-0.20240306115632-b2693620eff6
+	go.opentelemetry.io/collector/featuregate v1.3.1-0.20240306115632-b2693620eff6
 	go.opentelemetry.io/collector/pdata v1.3.1-0.20240306115632-b2693620eff6
 	go.opentelemetry.io/otel v1.24.0
 	go.opentelemetry.io/otel/metric v1.24.0
@@ -45,6 +46,7 @@ require (
 	github.com/golang/mock v1.6.0 // indirect
 	github.com/golang/protobuf v1.5.3 // indirect
 	github.com/google/uuid v1.6.0 // indirect
+	github.com/hashicorp/go-version v1.6.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/karrick/godirwalk v1.17.0 // indirect
 	github.com/knadh/koanf/maps v0.1.1 // indirect