Various Hunter's pride sprite improvments (shiptest-ss13#3943)

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Various minor hunter's pride improvements.

Gives derringer it's own new sprite

Sprites

![image](https://github.com/user-attachments/assets/a68dfe7a-4959-4e04-a7c4-5676348cfa60)

:cl:
add: Touches up the sprites of various hunter's pride thingys, notably
the hellfire and brimstone
add: Derringers have a new sprite
del: Double barreled shotgun reskins
/:cl:

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---------

Co-authored-by: retlaw34 <[email protected]>

code/modules/projectiles/guns/ballistic/pistol.dm

@@ -157,6 +157,7 @@
 	name = ".38 Derringer"
 	desc = "An easily concealable derringer. Uses .38 special ammo."
 	icon_state = "derringer"
+	item_state = "hp_generic"
 
 	icon = 'icons/obj/guns/manufacturer/hunterspride/48x32.dmi'
 	lefthand_file = 'icons/obj/guns/manufacturer/hunterspride/lefthand.dmi'
@@ -201,6 +202,7 @@
 	mob_overlay_icon = 'icons/obj/guns/manufacturer/scarborough/onmob.dmi'
 
 	icon_state = "derringer_syndie"
+	item_state = "sa_generic"
 	default_ammo_type = /obj/item/ammo_box/magazine/internal/derr357
 	allowed_ammo_types = list(
 		/obj/item/ammo_box/magazine/internal/derr357,

code/modules/projectiles/guns/manufacturer/hunter_pride/ballistics.dm

@@ -316,10 +316,6 @@ NO_MAG_GUN_HELPER(automatic/pistol/candor/factory)
 	)
 
 	obj_flags = UNIQUE_RENAME
-	unique_reskin = list("Default" = "dshotgun",
-						"Stainless Steel" = "dshotgun_white",
-						"Stained Green" = "dshotgun_green"
-						)
 	semi_auto = TRUE
 	can_be_sawn_off = TRUE
 	bolt_type = BOLT_TYPE_NO_BOLT