Some list optimizations, heretic ruins optimization (#94386)

code/datums/hud.dm

@@ -57,7 +57,7 @@ GLOBAL_LIST_INIT(trait_blockers_to_hud, list(
 	var/list/mob/hud_users_all_z_levels = list()
 
 	///these will be the indexes for the atom's hud_list
-	var/list/hud_icons = list()
+	var/list/hud_icons
 
 	///mobs associated with the next time this hud can be added to them
 	var/list/next_time_allowed = list()
@@ -75,6 +75,8 @@ GLOBAL_LIST_INIT(trait_blockers_to_hud, list(
 	for(var/z_level in 1 to world.maxz)
 		hud_atoms += list(list())
 		hud_users += list(list())
+	if(LAZYLEN(hud_icons))
+		hud_icons = string_list(hud_icons)
 
 	RegisterSignal(SSdcs, COMSIG_GLOB_NEW_Z, PROC_REF(add_z_level_huds))
 

code/game/atom/alternate_appearance.dm

@@ -110,6 +110,7 @@ GLOBAL_LIST_EMPTY(active_alternate_appearances)
 	)
 
 /datum/atom_hud/alternate_appearance/basic/New(key, image/I, options = AA_TARGET_SEE_APPEARANCE)
+	signals_registering = string_list(signals_registering)
 	..()
 	transfer_overlays = options & AA_MATCH_TARGET_OVERLAYS
 	image = I

code/game/objects/effects/blessing.dm

@@ -6,16 +6,22 @@
 	anchored = TRUE
 	density = FALSE
 	mouse_opacity = MOUSE_OPACITY_TRANSPARENT
+	/// Is this blessing visible to those with the ability to see blessed tiles? (chaplains)
+	var/invisible
 
 /obj/effect/blessing/Initialize(mapload)
 	. = ..()
+
+	RegisterSignal(loc, COMSIG_ATOM_INTERCEPT_TELEPORTING, PROC_REF(block_cult_teleport))
+
+	if(invisible)
+		return
+
 	var/image/blessing_icon = image(icon = 'icons/effects/effects.dmi', icon_state = "blessed", layer = ABOVE_NORMAL_TURF_LAYER, loc = src)
 	blessing_icon.alpha = 64
 	blessing_icon.appearance_flags = RESET_ALPHA
 	add_alt_appearance(/datum/atom_hud/alternate_appearance/basic/blessed_aware, "blessing", blessing_icon)
 
-	RegisterSignal(loc, COMSIG_ATOM_INTERCEPT_TELEPORTING, PROC_REF(block_cult_teleport))
-
 /obj/effect/blessing/Destroy()
 	UnregisterSignal(loc, COMSIG_ATOM_INTERCEPT_TELEPORTING)
 	return ..()
@@ -26,3 +32,6 @@
 
 	if(channel == TELEPORT_CHANNEL_CULT)
 		return TRUE
+
+/obj/effect/blessing/invisible
+	invisible = TRUE