GeoNodeStatus calculates numbers inefficiently

attachments_synced_count

In particular, there are a number of giant cross-database plucks that will need to be replaced with postgres_fdw when that is ready, but also consider this fragment:

  def attachments_synced_count
    @attachments_synced_count ||= begin
      upload_ids = attachments.pluck(:id)
      synced_ids = Geo::FileRegistry.where(file_type: [:attachment, :avatar, :file]).pluck(:file_id)

      (synced_ids & upload_ids).length
    end
  end

I think this could just be Geo::FileRegistry.where(file_type: [:attachment, :avatar, :file]).count

Also, a bug: we need personal_file in the list of types. this is fixed in https://gitlab.com/gitlab-org/gitlab-ee/issues/3691

restricted_project_ids

From gitlab-org/gitlab-ee#3932:

GeoNode#restricted_project_ids should be exposed as relation GeoNode#restricted_projects and only when it's really needed plucked to an array (see also discussion)