Automated bookkeeping areas from other mods are visible with Area Unlocker but not in vanilla.

[joshuafcole]

See linked discussion on PRF issue: zymex22/Project-RimFactory-Revived#340

Urgency

Very low -- just causes extra useless entries in the area list.

Problem description
PRF Uses a custom area type for tracking the areas their drones should manage. These areas are normally not visible in the areas list, but Area Unlocker makes them visible.

Describe the solution
The visibility check right now only checks area.Mutable Perhaps we can add another check to ensure they're a default allowed area rather than a custom modded area subclass?

Alternatives
We discussed making the areas immutable on the PRF side, but that doesn't fly since they need to be deleted if the drones-wielding machines are moved or destroyed.