Changes the default ghost lighting, makes it a preference (#65352)

* Changes the default ghost lighting, makes it a preference

I think the way ghost lighting looks right now is really crummy.
It's dark enough you can see where the shadows should be, but it's just
bright enough for everything to look like dog poo

A lot of what makes the game look nice is the depth of the lighting
and if we just hide that for observers we're shooting ourselves in the
foot.

I'm also making it a game preference, so if someone wants to have bad
opinions they can easily.

code/modules/mob/dead/observer/login.dm

@@ -21,5 +21,7 @@
 	update_icon(ALL, preferred_form)
 	updateghostimages()
 	client.set_right_click_menu_mode(FALSE)
+	lighting_alpha = default_lighting_alpha()
+	update_sight()
 
 

code/modules/mob/dead/observer/observer.dm

@@ -13,7 +13,7 @@ GLOBAL_VAR_INIT(observer_default_invisibility, INVISIBILITY_OBSERVER)
 	density = FALSE
 	see_invisible = SEE_INVISIBLE_OBSERVER
 	see_in_dark = 100
-	lighting_alpha = LIGHTING_PLANE_ALPHA_MOSTLY_INVISIBLE
+	lighting_alpha = LIGHTING_PLANE_ALPHA_MOSTLY_VISIBLE
 	invisibility = INVISIBILITY_OBSERVER
 	hud_type = /datum/hud/ghost
 	movement_type = GROUND | FLYING
@@ -150,6 +150,7 @@ GLOBAL_VAR_INIT(observer_default_invisibility, INVISIBILITY_OBSERVER)
 	data_huds_on = 1
 
 	SSpoints_of_interest.make_point_of_interest(src)
+	ADD_TRAIT(src, TRAIT_HEAR_THROUGH_DARKNESS, ref(src))
 
 /mob/dead/observer/get_photo_description(obj/item/camera/camera)
 	if(!invisibility || camera.see_ghosts)
@@ -1041,3 +1042,9 @@ This is the proc mobs get to turn into a ghost. Forked from ghostize due to comp
 			client.images += t_ray_images
 		else
 			client.images -= stored_t_ray_images
+
+/mob/dead/observer/default_lighting_alpha()
+	var/datum/preferences/prefs = client?.prefs
+	if(!prefs || (client?.combo_hud_enabled && prefs.toggles & COMBOHUD_LIGHTING))
+		return ..()
+	return GLOB.ghost_lighting_options[prefs.read_preference(/datum/preference/choiced/ghost_lighting)]