MM-45899: Insights: least active channels (#20796)

* Add api endpoints, app layers for top inactive channels with dummy store calls

* Add store functions for top inactive channels

* Add model, store, app tests.

* Add client function and api tests

* Add participants information to TopInactiveChannel

* Translation fix

* Style fix while writing response

* Return channelmember IDs instead of profiles, query in batch avoiding inside the loop

* Make the following changes

 - move DeleteAt to subqueries, to avoid select, group by
 - Remove TeamId from response
 - Count bots and webhook posts

* SQL query lint fix, store test fix to include bot messages

* make app-layers

* Fix empty participant lists being sent as [""]

* Track channel joins, to distinguish 0 activity channels vs new channels

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

model/client4.go

@@ -3642,6 +3642,41 @@ func (c *Client4) GetTopChannelsForUserSince(teamId string, timeRange string, pa
 	return topChannels, BuildResponse(r), nil
 }
 
+// GetTopInactiveChannelsForTeamSince will return an ordered list of the top channels in a given team.
+func (c *Client4) GetTopInactiveChannelsForTeamSince(teamId string, timeRange string, page int, perPage int) (*TopInactiveChannelList, *Response, error) {
+	query := fmt.Sprintf("?time_range=%v&page=%v&per_page=%v", timeRange, page, perPage)
+	r, err := c.DoAPIGet(c.teamRoute(teamId)+"/top/inactive_channels"+query, "")
+	if err != nil {
+		return nil, BuildResponse(r), err
+	}
+	defer closeBody(r)
+	var topInactiveChannels *TopInactiveChannelList
+	if jsonErr := json.NewDecoder(r.Body).Decode(&topInactiveChannels); jsonErr != nil {
+		return nil, nil, NewAppError("GetTopInactiveChannelsForTeamSince", "api.unmarshal_error", nil, jsonErr.Error(), http.StatusInternalServerError)
+	}
+	return topInactiveChannels, BuildResponse(r), nil
+}
+
+// GetTopInactiveChannelsForUserSince will return an ordered list of your top channels in a given team.
+func (c *Client4) GetTopInactiveChannelsForUserSince(teamId string, timeRange string, page int, perPage int) (*TopInactiveChannelList, *Response, error) {
+	query := fmt.Sprintf("?time_range=%v&page=%v&per_page=%v", timeRange, page, perPage)
+
+	if teamId != "" {
+		query += fmt.Sprintf("&team_id=%v", teamId)
+	}
+
+	r, err := c.DoAPIGet(c.usersRoute()+"/me/top/inactive_channels"+query, "")
+	if err != nil {
+		return nil, BuildResponse(r), err
+	}
+	defer closeBody(r)
+	var topInactiveChannels *TopInactiveChannelList
+	if jsonErr := json.NewDecoder(r.Body).Decode(&topInactiveChannels); jsonErr != nil {
+		return nil, nil, NewAppError("GetTopInactiveChannelsForUserSince", "api.unmarshal_error", nil, jsonErr.Error(), http.StatusInternalServerError)
+	}
+	return topInactiveChannels, BuildResponse(r), nil
+}
+
 // Post Section
 
 // CreatePost creates a post based on the provided post struct.