Function fetch_and_store 

pub(crate) async fn fetch_and_store(
    client: &Client,
    pool: &PgPool,
) -> Result<usize, FetchError>

Fetches the XLX reflector list and upserts all entries into Postgres.

Returns the number of reflectors successfully upserted. After upserting each reflector, also sets tier2_available = true since all XLX reflectors support the UDP JSON monitor protocol on port 10001.

Errors

• FetchError::Http if the HTTP request fails.
• FetchError::Xml if the XML response cannot be deserialized.
• FetchError::Database if any database operation fails.