Updates world icons for knives (#3663)

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## About The Pull Request


![image](https://github.com/user-attachments/assets/41a6de91-6054-41c5-9db7-09551d681209)

## Changelog

:cl:
imageadd: Updated world icons for knives
/:cl:

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code/game/objects/items/melee/knife.dm

@@ -1,7 +1,8 @@
 /obj/item/melee/knife
 	icon_state = "kitchenknife"
 	item_state = "kitchenknife"
-	icon = 'icons/obj/weapon/knife.dmi'
+	icon = 'icons/obj/weapon/knives/knife.dmi'
+	world_file = 'icons/obj/weapon/knives/knife_world.dmi'
 	lefthand_file = 'icons/mob/inhands/weapons/knifes_lefthand.dmi'
 	righthand_file = 'icons/mob/inhands/weapons/knifes_righthand.dmi'
 	pickup_sound =  'sound/items/handling/knife1_pickup.ogg'
@@ -105,7 +106,6 @@
 	force = 20
 	throwforce = 20
 	attack_verb = list("slashed", "stabbed", "sliced", "torn", "ripped", "cut")
-	world_file = 'icons/obj/world/melee.dmi'
 
 /obj/item/melee/knife/survival
 	name = "survival knife"
@@ -116,7 +116,6 @@
 	force = 15
 	throwforce = 15
 	attack_verb = list("slashed", "stabbed", "sliced", "torn", "ripped", "cut")
-	world_file = 'icons/obj/world/melee.dmi'
 
 /obj/item/melee/knife/bone
 	name = "bone dagger"
@@ -129,7 +128,6 @@
 	force = 15
 	throwforce = 15
 	custom_materials = null
-	world_file = 'icons/obj/world/melee.dmi'
 
 /obj/item/melee/knife/combat/cyborg
 	name = "cyborg knife"