kv/kvclient: set activeRangefeed NodeID and ReplicaID earlier

Previously, we only set the NodeID and ReplicaID on receipt of the
first rangefeed message.

That meant that if a rangefeed was waiting on the catchup iterator
semaphore, we couldn't see which node or replica it was running on in
the crdb_internal.active_range_feeds table.

Here, we add these fields before making the rangefeed request.

Epic: none
Release note: None

pkg/kv/kvclient/kvcoord/dist_sender_mux_rangefeed.go

@@ -214,7 +214,7 @@ func (m *rangefeedMuxer) startSingleRangeFeed(
 	stream := &activeMuxRangeFeed{
 		// TODO(msbutler): It's sad that there's a bunch of repeat metadata.
 		// Deduplicate once old style rangefeed code is banished from the codebase.
-		activeRangeFeed:         newActiveRangeFeed(span, startAfter, m.registry, m.metrics, parentRangefeedMetadata),
+		activeRangeFeed:         newActiveRangeFeed(span, startAfter, m.registry, m.metrics, parentRangefeedMetadata, token.Desc().RangeID),
 		rSpan:                   rs,
 		startAfter:              startAfter,
 		token:                   token,
@@ -287,6 +287,11 @@ func (s *activeMuxRangeFeed) start(ctx context.Context, m *rangefeedMuxer) error
 			args.Replica = s.transport.NextReplica()
 			args.StreamID = streamID
 			s.ReplicaDescriptor = args.Replica
+
+			s.activeRangeFeed.Lock()
+			s.activeRangeFeed.NodeID = args.Replica.NodeID
+			s.activeRangeFeed.Unlock()
+
 			rpcClient, err := s.transport.NextInternalClient(ctx)
 			if err != nil {
 				log.VErrEventf(ctx, 1, "RPC error connecting to replica %s: %s", args.Replica, err)

pkg/kv/kvclient/kvcoord/dist_sender_rangefeed.go

@@ -496,6 +496,7 @@ func newActiveRangeFeed(
 	rr *rangeFeedRegistry,
 	metrics *DistSenderRangeFeedMetrics,
 	parentMetadata parentRangeFeedMetadata,
+	initialRangeID roachpb.RangeID,
 ) *activeRangeFeed {
 	// Register partial range feed with registry.
 	active := &activeRangeFeed{
@@ -504,6 +505,7 @@ func newActiveRangeFeed(
 			StartAfter:              startAfter,
 			ParentRangefeedMetadata: parentMetadata,
 			CreatedTime:             timeutil.Now(),
+			RangeID:                 initialRangeID,
 		},
 	}