[Broken functionality] Donor Wall should display donor names and avatar initials for plain-text donation meta

[dugasignal]

User Story

As a site administrator using the GiveWP Donor Wall, I want donor names and avatar initials to be displayed correctly so that public donor information is shown as configured.

Details

The Donor Wall renders donor names and fallback initials as empty for newer donations, even though the donor name is correctly stored in the donation meta and is visible in the GiveWP admin interface.

This happens because get_donation_data() in:

includes/donors/class-give-donor-wall.php

currently uses:

$temp[ $result->{$donation_id_col} ][ $result->meta_key ] =
    unserialize( $result->meta_value, [ 'allowed_classes' => false ] );

Fix: use maybe_unserialize() instead of unserialize() when reading Donor Wall meta values