Fixes water overlays showing on toilets facing directions other than SOUTH (#86878)

## About The Pull Request
The overlays shows on directions other than south because the code
doesn't update the overlays whenever the dir is changed.
Honestly saving a tiny blip of space with a pair of 1-dir static icons
isn't worth making all this messy code over anyway, so I just scratched
all of it and gave the icon state 4 dirs (3 of which are empty but that
may change if someone decides to give the toilet
a 3/4 perspective when facing right or left.

## Why It's Good For The Game
Fixed water overlays showing on toilets facing directions other than
SOUTH (down).

## Changelog

🆑
fix: Fixed water overlays showing on toilets facing directions other
than SOUTH (down).
/🆑

code/game/objects/structures/water_structures/toilet.dm

@@ -25,13 +25,9 @@
 	var/list/cistern_items
 	///Lazylist of fish in the toilet, not to be mixed with the items in the cistern. Max of 3
 	var/list/fishes
-	///Static toilet water overlay given to toilets that are facing a direction we can see the water in.
-	var/static/mutable_appearance/toilet_water_overlay
 
 /obj/structure/toilet/Initialize(mapload)
 	. = ..()
-	if(isnull(toilet_water_overlay))
-		toilet_water_overlay = mutable_appearance(icon, "[base_icon_state]-water")
 	cover_open = round(rand(0, 1))
 	update_appearance(UPDATE_ICON)
 	if(mapload && SSmapping.level_trait(z, ZTRAIT_STATION))
@@ -176,8 +172,8 @@
 
 /obj/structure/toilet/update_overlays()
 	. = ..()
-	if(!flushing && cover_open && (dir & SOUTH))
-		. += toilet_water_overlay
+	if(!flushing && cover_open)
+		. += "[base_icon_state]-water"
 
 /obj/structure/toilet/atom_deconstruct(dissambled = TRUE)
 	for(var/obj/toilet_item in cistern_items)