Magento 2 "Area Code Not Set" and "Already Set" Errors: The Fix
The Magento 2 "Area code not set" and "Area code is already set" errors both come from one rule about when an area must exist. This guide fixes them fix-first for Magento 2.4.4 to 2.4.9 in custom console commands, bootstrap scripts, setup patches, and indexers, with full runnable code.