gitserver: Move search observability (#61859)

Now co-located with the code it is observing.

Test plan:

N/a, moved code only.

Author: eseliger

cmd/gitserver/internal/search.go

@@ -8,6 +8,8 @@ import (
 	"sync/atomic"
 	"time"
 
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
 	"github.com/sourcegraph/log"
 	"go.opentelemetry.io/otel/attribute"
 
@@ -21,6 +23,23 @@ import (
 	"github.com/sourcegraph/sourcegraph/internal/trace"
 )
 
+var (
+	searchRunning = promauto.NewGauge(prometheus.GaugeOpts{
+		Name: "src_gitserver_search_running",
+		Help: "number of gitserver.Search running concurrently.",
+	})
+	searchDuration = promauto.NewHistogramVec(prometheus.HistogramOpts{
+		Name:    "src_gitserver_search_duration_seconds",
+		Help:    "gitserver.Search duration in seconds.",
+		Buckets: []float64{0.01, 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 30},
+	}, []string{"error"})
+	searchLatency = promauto.NewHistogram(prometheus.HistogramOpts{
+		Name:    "src_gitserver_search_latency_seconds",
+		Help:    "gitserver.Search latency (time until first result is sent) in seconds.",
+		Buckets: []float64{0.01, 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 30},
+	})
+)
+
 func searchWithObservability(ctx context.Context, logger log.Logger, repoDir common.GitDir, tr trace.Trace, args *protocol.SearchRequest, onMatch func(*protocol.CommitMatch) error) (limitHit bool, err error) {
 	searchStart := time.Now()
 

cmd/gitserver/internal/server.go

@@ -721,21 +721,6 @@ func scanCRLF(data []byte, atEOF bool) (advance int, token []byte, err error) {
 }
 
 var (
-	searchRunning = promauto.NewGauge(prometheus.GaugeOpts{
-		Name: "src_gitserver_search_running",
-		Help: "number of gitserver.Search running concurrently.",
-	})
-	searchDuration = promauto.NewHistogramVec(prometheus.HistogramOpts{
-		Name:    "src_gitserver_search_duration_seconds",
-		Help:    "gitserver.Search duration in seconds.",
-		Buckets: []float64{0.01, 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 30},
-	}, []string{"error"})
-	searchLatency = promauto.NewHistogram(prometheus.HistogramOpts{
-		Name:    "src_gitserver_search_latency_seconds",
-		Help:    "gitserver.Search latency (time until first result is sent) in seconds.",
-		Buckets: []float64{0.01, 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 30},
-	})
-
 	pendingClones = promauto.NewGauge(prometheus.GaugeOpts{
 		Name: "src_gitserver_clone_queue",
 		Help: "number of repos waiting to be cloned.",