The rewrite in #2773 introduced a bug (identified by KMFrench on Discord) where
nestboxes themselves would be forbidden, which prevents egglaying citizens from
using them since the nestboxes would be claimed before use. The previous version
of the plugin handled this by skipping the first item in `contained_items`,
which is the building material (in this case, the nestbox).
This fix limits the `forbid` flag manipulation to egg items only, which should
be a reasonable limitation that still allows the plugin to serve its purpose.
lethosor
Myk Taylor
Kelly Kinkade