Removes hacky see in darkness invisibility bullshit, uses planes. (#25931)

* Removes hacky see in darkness invisibility bullshit, uses planes.

Also removed the use of invisibility for ghosts of others, instead using override images.

Per client lighting visibility now has 4 levels, all on, all off, and two midways, this allows for things to be able to see in the dark while still being able to see what is dark and what has light, ghosts and aliens and other shit can cycle between all 4, other things were given one of the 3 values depending.

* Remove qdel global var search.

* Cleans up code, makes changing lighting/NV level easier.

code/game/gamemodes/blob/overmind.dm

@@ -7,13 +7,12 @@
 	mouse_opacity = 1
 	move_on_shuttle = 1
 	see_in_dark = 8
-	see_invisible = SEE_INVISIBLE_MINIMUM
 	invisibility = INVISIBILITY_OBSERVER
 	layer = FLY_LAYER
 
 	pass_flags = PASSBLOB
 	faction = list("blob")
-
+	lighting_alpha = LIGHTING_PLANE_ALPHA_MOSTLY_INVISIBLE
 	var/obj/structure/blob/core/blob_core = null // The blob overmind's core
 	var/blob_points = 0
 	var/max_blob_points = 100
@@ -21,7 +20,6 @@
 	var/datum/reagent/blob/blob_reagent_datum = new/datum/reagent/blob()
 	var/list/blob_mobs = list()
 	var/list/resource_blobs = list()
-	var/ghostimage = null
 	var/free_chem_rerolls = 1 //one free chemical reroll
 	var/nodes_required = 1 //if the blob needs nodes to place resource and factory blobs
 	var/placed = 0
@@ -52,9 +50,6 @@
 	if(blob_core)
 		blob_core.update_icon()
 
-	ghostimage = image(src.icon,src,src.icon_state)
-	GLOB.ghost_darkness_images |= ghostimage //so ghosts can see the blob cursor when they disable darkness
-	updateallghostimages()
 	..()
 
 /mob/camera/blob/Life()
@@ -82,11 +77,7 @@
 			BM.overmind = null
 			BM.update_icons()
 	GLOB.overminds -= src
-	if(ghostimage)
-		GLOB.ghost_darkness_images -= ghostimage
-		qdel(ghostimage)
-		ghostimage = null
-		updateallghostimages()
+
 	return ..()
 
 /mob/camera/blob/Login()