A dedicated server's debug.txt grew 2 GB in 12 hours, almost all of it
"maximum light cluster references per map (8192) exceeded", written each
time a light could not join a cluster: thousands of times a second on a
busy map. A full reference list now says so the first time a map, and the
times after are counted and told when the map's lists are let go or made
anew. What fits in the lists is as before.
The dedicated server draws nothing, and a light's clusters are only used
to draw (the lights of an object or the map, and a unit's illumination,
which only debug_unit_illumination reads, from the lights drawn that
frame). The server (HALO_SERVER) no longer joins lights to clusters, so
it does none of that work each tick and never fills the lists.
(cherry picked from commit 50cc6274fb5f7697c6f3c25394e15e22f87106f2)
Milenko