Update SSOverlays (ported from Baystation) (#19051)

Our SSOverlays system is outdated, and is likely the cause of many of
the issues seen in #18895. It has also been linked to a massive server
performance decrease.

This brings an updated system from Baystation, hopefully with speed
increases.

Should be testmerged, ideally with #18895.

---------

Co-authored-by: Cody Brittain <cbrittain10@live.com>

code/ZAS/Debug.dm

@@ -12,8 +12,8 @@ var/image/mark = image('icons/zone.dmi', icon_state = "mark")
 /turf/var/tmp/dbg_img
 /turf/proc/dbg(image/img, d = 0)
 	if(d > 0) img.dir = d
-	cut_overlay(dbg_img)
-	add_overlay(img)
+	CutOverlays(dbg_img)
+	AddOverlays(img)
 	dbg_img = img
 
 /proc/soft_assert(thing,fail)