place required ruins in decreasing order of size (#29576)

code/__HELPERS/cmp.dm

@@ -60,3 +60,6 @@
 
 /proc/cmp_changeling_power_category_asc(datum/changeling_power_category/a, datum/changeling_power_category/b)
 	return initial(a.priority) - initial(b.priority)
+
+/proc/cmp_ruin_placement_cost(datum/map_template/ruin/A, datum/map_template/ruin/B)
+	return A.get_cost() - B.get_cost()

code/datums/mapping/ruin_placer.dm

@@ -149,6 +149,7 @@
 			continue
 		ruins_available[R] = R.placement_weight
 
+	forced_ruins = sortTim(forced_ruins, GLOBAL_PROC_REF(cmp_ruin_placement_cost))
 	while(length(forced_ruins))
 		var/datum/map_template/ruin/ruin = forced_ruins[length(forced_ruins)]
 		var/datum/ruin_placement/placement = new(ruin, base_padding_ = base_padding)