Converts pre-rework generic heretic gear into chaplain clothing and a null rod (#94363)

## About The Pull Request

Reused the old pre-rework heretic robe and blade assets as a new set of
chaplain gear and null rod option.

Replaced the last few existing uses of the now spriteless generic robe:
- Deathmatch, changed heretic warrior to use blade robes
- Deathmatch, changed ripper to use the new chaplain armour
- Tribal mothman legion corpse, changed to use new chaplain armour
- Heretic preview and hallucination, changed to use rust robes
- Heretic virtual domain, changed to use rust robes

<img width="127" height="131" alt="image"
src="https://github.com/user-attachments/assets/690e848e-5191-44d4-bd58-5e338fa2aa4e"
/>

## Why It's Good For The Game

Chaplains are the playground of old magic content assets, where they
find a second life as cosplay outfits. Chaplains can already cosplay
cultists, it's only fair that they can pretend to be a heretic as well.

## Changelog
🆑
add: Added a new set of chaplain armour based on the generic heretic
robes unavailable since the path rework.
/🆑

code/modules/mob_spawn/corpses/mining_corpses.dm

@@ -388,8 +388,8 @@
 /datum/outfit/consumed_heremoth
 	name = "Legion-Consumed Tribal Mothman"
 	uniform = /obj/item/clothing/under/costume/loincloth
-	suit = /obj/item/clothing/suit/hooded/cultrobes/eldritch
-	head = /obj/item/clothing/head/hooded/cult_hoodie/eldritch
+	suit = /obj/item/clothing/suit/chaplainsuit/armor/heretic
+	head = /obj/item/clothing/head/helmet/chaplain/heretic
 
 /datum/outfit/consumed_heremoth/pre_equip(mob/living/carbon/human/moth, visuals_only = FALSE)
 	if(!visuals_only)