camera/autoname/LateInitialize() optimization (#3001)

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## About The Pull Request
copys tgstation/tgstation#70969 
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## Why It's Good For The Game
I noticed we search glob.machines for every autoname camera which cannot
be better then a static list
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## Changelog

:cl:
code: camera/autoname/LateInitialize() optimization
/:cl:

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code/game/machinery/camera/presets.dm

@@ -56,18 +56,11 @@
 
 /obj/machinery/camera/autoname/LateInitialize()
 	. = ..()
-	number = 1
-	var/area/A = get_area(src)
-	if(A)
-		for(var/obj/machinery/camera/autoname/C in GLOB.machines)
-			if(C == src)
-				continue
-			var/area/CA = get_area(C)
-			if(CA.type == A.type)
-				if(C.number)
-					number = max(number, C.number+1)
-		c_tag = "[A.name] #[number]"
-
+	var/static/list/autonames_in_areas = list()
+	var/area/camera_area = get_area(src)
+	number = autonames_in_areas[camera_area] + 1
+	autonames_in_areas[camera_area] = number
+	c_tag = "[format_text(camera_area.name)] #[number]"
 
 // UPGRADE PROCS