up ports the TG overlays subsystem update (#18945)

* up ports the TG overlays subsystem update

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* for spell

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* cutting

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Co-authored-by: Cameron Lennox <killer65311@gmail.com>

code/modules/mob/living/living.dm

@@ -3,6 +3,7 @@
 
 	//Prime this list if we need it.
 	if(has_huds)
+		// Note, this should be refactored to drop priority overlays
 		add_overlay(backplane,TRUE) //Strap this on here, to block HUDs from appearing in rightclick menus: http://www.byond.com/forum/?post=2336679
 		hud_list = list()
 		hud_list.len = TOTAL_HUDS

code/modules/mob/living/simple_mob/subtypes/blob/spore.dm

@@ -94,7 +94,7 @@
 		if(overmind)
 			blob_head_overlay.color = overmind.blob_type.complementary_color
 		color = initial(color)//looks better.
-		add_overlay(blob_head_overlay, TRUE)
+		add_overlay(blob_head_overlay)
 
 /mob/living/simple_mob/blob/spore/handle_special()
 	..()