Add debug for player bird spawning

[pridit]

I need some reporting on instances of players spawning as birds. My only known occurrence is when the group limit has been hit (144), but this was reported recently fairly close to the mission start so it may not be the only case unless there is some way or bug that spams groups.

Add some logging:

• When group limit is approaching or at 144
• When player unit class is bird (test that this ever evaluates)

It would also be useful for some admin ability to check all existing group formations on the map in a toggleable way once in-game.