Fix #1361,#1459 (Makes constructs immune to ZAS stun)

Now properly overrides ZAS procs airflow_stun() and airflow_hit() for constructs.
They don't have the right code to handle stuns, so they were getting perma-stunned with no way to recover outside of varediting.
Fixes #1361 and #1459 (construct permastun).
Tested and working.