pub async fn insert(
    conn: &mut PgConnection,
    pkey_policy: PKeyPolicy<Uuid>,
    page_id: Uuid,
    title: &str,
    content: &PageHistoryContent,
    history_change_reason: HistoryChangeReason,
    author_user_id: Uuid,
    restored_from_id: Option<Uuid>
) -> ModelResult<Uuid>