feat: add trusted proxy identity and overload stats

transport/native/server_test.go

@@ -711,6 +711,9 @@ func TestServerConcurrentRequestLimit(t *testing.T) {
 	if response.StatusCode != http.StatusServiceUnavailable {
 		t.Fatalf("expected 503 at concurrency limit, got %d", response.StatusCode)
 	}
+	if stats := server.Stats(); stats.RejectedRequests != 1 {
+		t.Fatalf("expected one rejected request, got %+v", stats)
+	}
 	close(release)
 	response, err = http.ReadResponse(bufio.NewReader(first), &http.Request{Method: http.MethodGet})
 	if err != nil {
@@ -842,6 +845,9 @@ func TestServerConnectionLimitReleasesAfterRequest(t *testing.T) {
 		t.Fatal("connection over MaxConnections was not rejected")
 	}
 	second.Close()
+	if stats := server.Stats(); stats.RejectedConnections < 1 {
+		t.Fatalf("expected rejected connection counter, got %+v", stats)
+	}
 
 	close(release)
 	firstResponse, err := http.ReadResponse(bufio.NewReader(first), &http.Request{Method: http.MethodGet})