[MM-42739] Insights - Top Channels API Endpoint (#19953)

* [MM-42739] Initial setup for top channels for team

* [MM-42739] Add initial tests

* [MM-42739] Update tests

* [MM-42739] Add top channels for user

* [MM-42739] Fix query

* [MM-42739] Update query

* [MM-42739] Improve query performance

* [MM-42739] Remove rank

* [MM-42739] Fix tests to use new time range today

* [MM-42739] Add tests for top channels for user

* [MM-42739] Add test for pagination

* Remove top channels by time struct

* [MM-42739] Update test names

* [MM-42739] Remove rank from top reactions

* [MM-42739] Return empty array instead of nil when result is empty

* [MM-42739] Add additional tests and update permissions check for teams

* [MM-42739] Add excluded channel tests for top reactions

* [MM-42739] Move insights to api4/insights and keep time range as string until required

* [MM-42739] Update queries only check DeleteAt after union

* [MM-42739] Improve query performance by using publicchannels table

* [MM-42739] Fix broken query after merge

store/timerlayer/timerlayer.go

@@ -1605,6 +1605,38 @@ func (s *TimerLayerChannelStore) GetTeamMembersForChannel(channelID string) ([]s
 	return result, err
 }
 
+func (s *TimerLayerChannelStore) GetTopChannelsForTeamSince(teamID string, userID string, since int64, offset int, limit int) (*model.TopChannelList, error) {
+	start := timemodule.Now()
+
+	result, err := s.ChannelStore.GetTopChannelsForTeamSince(teamID, userID, since, offset, limit)
+
+	elapsed := float64(timemodule.Since(start)) / float64(timemodule.Second)
+	if s.Root.Metrics != nil {
+		success := "false"
+		if err == nil {
+			success = "true"
+		}
+		s.Root.Metrics.ObserveStoreMethodDuration("ChannelStore.GetTopChannelsForTeamSince", success, elapsed)
+	}
+	return result, err
+}
+
+func (s *TimerLayerChannelStore) GetTopChannelsForUserSince(userID string, teamID string, since int64, offset int, limit int) (*model.TopChannelList, error) {
+	start := timemodule.Now()
+
+	result, err := s.ChannelStore.GetTopChannelsForUserSince(userID, teamID, since, offset, limit)
+
+	elapsed := float64(timemodule.Since(start)) / float64(timemodule.Second)
+	if s.Root.Metrics != nil {
+		success := "false"
+		if err == nil {
+			success = "true"
+		}
+		s.Root.Metrics.ObserveStoreMethodDuration("ChannelStore.GetTopChannelsForUserSince", success, elapsed)
+	}
+	return result, err
+}
+
 func (s *TimerLayerChannelStore) GroupSyncedChannelCount() (int64, error) {
 	start := timemodule.Now()