Easy Appointments <= 3.12.27 - Missing Authorization to Authenticated (Contributor+) Arbitrary Connection Deletion

The Easy Appointments plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check and missing nonce verification on the `ea_delete_multiple_connections` AJAX action in all versions up to, and including, 3.12.27. This makes it possible for authenticated attackers, with Contributor-level access and above, to delete arbitrary connection records from the `wp_ea_connections` table, disrupting the plugin's core booking functionality.