- distance is INFINITE, 0, or a positive integer based on get_dist() between
the examiner and examinee's turfs when they are on the same Z. When the
examiner is dead or a ghost, distance is always 0.
- also updates /examine( implementations to use it!
- adds w_class_to_name proc for reusing "It is a X item." examine behavior.
- Infinite powersource, Infinite grid load (powersink without boom) and APC dummy load.
- Not buildable, intended primarily for debugging or admin shenanigans. For mapped-in variants setting show_extended_information = FALSE is recommended.