adding rtc_init stat (#1316)

* adding rtc_initiated stat

* clean up signal and rtc init/connected

* update naming and break out stats update funcs

* update protocol dependency

pkg/routing/localrouter.go

@@ -8,6 +8,7 @@ import (
 	"go.uber.org/atomic"
 	"google.golang.org/protobuf/proto"
 
+	"github.com/livekit/livekit-server/pkg/telemetry/prometheus"
 	"github.com/livekit/protocol/livekit"
 	"github.com/livekit/protocol/logger"
 	"github.com/livekit/protocol/utils"
@@ -82,6 +83,7 @@ func (r *LocalRouter) ListNodes() ([]*livekit.Node, error) {
 }
 
 func (r *LocalRouter) StartParticipantSignal(ctx context.Context, roomName livekit.RoomName, pi ParticipantInit) (connectionID livekit.ConnectionID, reqSink MessageSink, resSource MessageSource, err error) {
+	prometheus.IncrementParticipantRtcInit(1)
 	// treat it as a new participant connecting
 	if r.onNewParticipant == nil {
 		err = ErrHandlerNotDefined

pkg/routing/redisrouter.go

@@ -207,6 +207,7 @@ func (r *RedisRouter) WriteNodeRTC(_ context.Context, rtcNodeID string, msg *liv
 }
 
 func (r *RedisRouter) startParticipantRTC(ss *livekit.StartSession, participantKey livekit.ParticipantKey, participantKeyB62 livekit.ParticipantKey) error {
+	prometheus.IncrementParticipantRtcInit(1)
 	// find the node where the room is hosted at
 	rtcNode, err := r.GetNodeForRoom(r.ctx, livekit.RoomName(ss.RoomName))
 	if err != nil {