Add debug mode for avatar modifier area

Avatar modifier areas are hard to position bc you need to guess where they are
It would be great to add a `debugMode` flag to show what area the box is covering, just like we do with the TriggerComponent

Start by locating the avatar modifier area implementation and the TriggerComponent's existing debugMode behavior. Compare how that mode exposes its covered area, then determine where the avatar modifier flag belongs. Done means the modifier area can be visibly identified while debug mode is enabled, matching the issue's positioning goal.

Written by the indexing model from the issue text.