code: func IncludeBacklogTotalCount(ctx context.Context, db application.DB) SpaceConvertFunc {
  	return func(req *http.Request, modelSpace *space.Space, appSpace *app.Space) error {
  		count, err := countBacklogItems(ctx, db, modelSpace.ID)
  		if err != nil {
  			return errs.Wrap(err, "unable to count backlog items")
  		}
  		appSpace.Links.Backlog.Meta = &app.BacklogLinkMeta{TotalCount: count} // TODO (xcoulon) remove that part
  		appSpace.Relationships.Backlog.Meta = map[string]interface{}{"totalCount": count}
  		return nil
  	}
  }
docs: // IncludeBacklog returns a SpaceConvertFunc that includes the a link to the backlog
  // along with the total count of items in the backlog of the current space