MM-33708 - Add MentionCountRoot column to ChannelMembers (#17099)

* added new column for root-only mentions

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

store/timerlayer/timerlayer.go

@@ -1431,10 +1431,10 @@ func (s *TimerLayerChannelStore) GroupSyncedChannelCount() (int64, error) {
 	return result, err
 }
 
-func (s *TimerLayerChannelStore) IncrementMentionCount(channelID string, userId string, updateThreads bool) error {
+func (s *TimerLayerChannelStore) IncrementMentionCount(channelID string, userId string, updateThreads bool, isRoot bool) error {
 	start := timemodule.Now()
 
-	err := s.ChannelStore.IncrementMentionCount(channelID, userId, updateThreads)
+	err := s.ChannelStore.IncrementMentionCount(channelID, userId, updateThreads, isRoot)
 
 	elapsed := float64(timemodule.Since(start)) / float64(timemodule.Second)
 	if s.Root.Metrics != nil {
@@ -1952,10 +1952,10 @@ func (s *TimerLayerChannelStore) UpdateLastViewedAt(channelIds []string, userId
 	return result, err
 }
 
-func (s *TimerLayerChannelStore) UpdateLastViewedAtPost(unreadPost *model.Post, userID string, mentionCount int, updateThreads bool) (*model.ChannelUnreadAt, error) {
+func (s *TimerLayerChannelStore) UpdateLastViewedAtPost(unreadPost *model.Post, userID string, mentionCount int, mentionCountRoot int, updateThreads bool) (*model.ChannelUnreadAt, error) {
 	start := timemodule.Now()
 
-	result, err := s.ChannelStore.UpdateLastViewedAtPost(unreadPost, userID, mentionCount, updateThreads)
+	result, err := s.ChannelStore.UpdateLastViewedAtPost(unreadPost, userID, mentionCount, mentionCountRoot, updateThreads)
 
 	elapsed := float64(timemodule.Since(start)) / float64(timemodule.Second)
 	if s.Root.Metrics != nil {
@@ -7096,22 +7096,6 @@ func (s *TimerLayerThreadStore) GetThreadForUser(userId string, teamId string, t
 	return result, err
 }
 
-func (s *TimerLayerThreadStore) GetThreadMentionsForUserPerChannel(userId string, teamId string) (map[string]int64, error) {
-	start := timemodule.Now()
-
-	result, err := s.ThreadStore.GetThreadMentionsForUserPerChannel(userId, teamId)
-
-	elapsed := float64(timemodule.Since(start)) / float64(timemodule.Second)
-	if s.Root.Metrics != nil {
-		success := "false"
-		if err == nil {
-			success = "true"
-		}
-		s.Root.Metrics.ObserveStoreMethodDuration("ThreadStore.GetThreadMentionsForUserPerChannel", success, elapsed)
-	}
-	return result, err
-}
-
 func (s *TimerLayerThreadStore) GetThreadsForUser(userId string, teamId string, opts model.GetUserThreadsOpts) (*model.Threads, error) {
 	start := timemodule.Now()