Fixes waterpacks and friends not GCing (#19269)

Move nozzles to Initialize
Makes reagents not hold a reference to their atom when they get destroyed

code/game/objects/items/weapons/extinguisher.dm

@@ -45,10 +45,11 @@
 	. += "<span class='notice'>The safety is [safety ? "on" : "off"].</span>"
 
 
-/obj/item/extinguisher/New()
-	..()
-	create_reagents(max_water)
-	reagents.add_reagent("water", max_water)
+/obj/item/extinguisher/Initialize(mapload)
+	. = ..()
+	if(!reagents)
+		create_reagents(max_water)
+		reagents.add_reagent("water", max_water)
 
 /obj/item/extinguisher/attack_self(mob/user as mob)
 	safety = !safety

code/game/objects/items/weapons/tanks/watertank.dm

@@ -128,16 +128,16 @@
 
 	var/obj/item/watertank/tank
 
-/obj/item/reagent_containers/spray/mister/New(parent_tank)
-	..()
-	if(check_tank_exists(parent_tank, src))
-		tank = parent_tank
-		reagents = tank.reagents	//This mister is really just a proxy for the tank's reagents
-		loc = tank
-	return
+/obj/item/reagent_containers/spray/mister/Initialize(mapload)
+	if(!check_tank_exists(loc, src))
+		return INITIALIZE_HINT_QDEL
+	tank = loc
+	reagents = tank.reagents	//This mister is really just a proxy for the tank's reagents
+	return ..()
 
 /obj/item/reagent_containers/spray/mister/Destroy()
 	tank = null
+	reagents = null // Unset, this is the tanks reagents
 	return ..()
 
 /obj/item/reagent_containers/spray/mister/dropped(mob/user as mob)
@@ -151,11 +151,9 @@
 
 /proc/check_tank_exists(parent_tank, mob/living/carbon/human/M, obj/O)
 	if(!parent_tank || !istype(parent_tank, /obj/item/watertank))	//To avoid weird issues from admin spawns
-		M.unEquip(O)
-		qdel(0)
-		return 0
+		return FALSE
 	else
-		return 1
+		return TRUE
 
 /obj/item/reagent_containers/spray/mister/Move()
 	..()
@@ -239,14 +237,20 @@
 	var/metal_synthesis_cooldown = 0
 	var/nanofrost_cooldown = 0
 
-/obj/item/extinguisher/mini/nozzle/New(parent_tank)
-	. = ..()
-	if(check_tank_exists(parent_tank, src))
-		tank = parent_tank
-		reagents = tank.reagents
-		max_water = tank.volume
-		loc = tank
-	return
+/obj/item/extinguisher/mini/nozzle/Initialize(mapload)
+	if(!check_tank_exists(loc, src))
+		return INITIALIZE_HINT_QDEL
+
+	tank = loc
+	reagents = tank.reagents
+	max_water = tank.volume
+
+	return ..()
+
+/obj/item/extinguisher/mini/nozzle/Destroy()
+	tank = null
+	reagents = null // Unset, this is the tanks reagents
+	return ..()
 
 /obj/item/extinguisher/mini/nozzle/Move()
 	..()