code: func (m *GormIterationRepository) Root(ctx context.Context, spaceID uuid.UUID) (*Iteration, error) {
  	defer goa.MeasureSince([]string{"goa", "db", "iteration", "query"}, time.Now())
  	var itr Iteration
  
  	tx := m.db.Where("space_id = ? AND nlevel(path)=1", spaceID).First(&itr)
  	if tx.Error != nil {
  		log.Error(ctx, map[string]interface{}{
  			"space_id": spaceID,
  			"err":      tx.Error,
  		}, "unable to get the root iteration")
  		if tx.Error == gorm.ErrRecordNotFound {
  			return nil, errors.NewNotFoundError("root iteration for space", spaceID.String())
  		}
  		return nil, errors.NewInternalError(ctx, tx.Error)
  	}
  	return &itr, nil
  }
docs: // Root returns the Root Iteration for a space