IO/FTL Can Buy Welding Visor + M12 Helm Holds 2 Visors (#4263)

# About the pull request

Intel Officers and Fire Team Leaders can now purchase a Welding Visor,
the price remains consistant with the welding goggle price.

Furthermore, the M12 Helmet (Nominally used by FTL's, IO's and other
officers) can have up to two visors inserted instead of only one.
Allowing someone to place both a welding visor and a medical visor (or
security visor?) inside the helmet.

# Explain why it's good for the game

Increases gameplay variety for IO's/FTLs wanting a combo of a medical
hud and welding visor. Many IOs and FTL's often don't take advantage of
their ability to perform engineering work, so rewarding a proactive user
with the ability to use a medical and welding visor seems justifiable,
especially as they need to expend precious (and limited) points to
purchase something that can not be acquired anywhere else on the
Almayer.


# Testing Photographs and Procedure
<details>
<summary>Screenshots & Videos</summary>

Put screenshots and videos here with an empty line between the
screenshots and the `<details>` tags.

</details>


# Changelog
:cl:
add: IO's and FTL's can now purchase a 'welding visor' from their
vendor. This visor grants whichever helmet it is attached with the
ability to flip a protective visor that prevents the user's eyes from
taking damage while welding.
balance: The M12 Helmet, normally used by FTL's and USCM Officers, can
mount two visors at once, instead of only one.
/:cl:

---------

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

code/game/machinery/vending/vendor_types/intelligence_officer.dm

@@ -14,8 +14,9 @@ GLOBAL_LIST_INIT(cm_vending_gear_intelligence_officer, list(
 		list("Fulton Recovery Device", 10, /obj/item/stack/fulton, null, VENDOR_ITEM_REGULAR),
 		list("Motion Detector", 15, /obj/item/device/motiondetector, null, VENDOR_ITEM_RECOMMENDED),
 		list("Plastic Explosive", 10, /obj/item/explosive/plastic, null, VENDOR_ITEM_REGULAR),
-		list("Welding Goggles", 5, /obj/item/clothing/glasses/welding, null, VENDOR_ITEM_REGULAR),
+		list("Welding Visor", 5, /obj/item/device/helmet_visor/welding_visor, null, VENDOR_ITEM_REGULAR),
 		list("Medical Helmet Optic", 5, /obj/item/device/helmet_visor/medical, null, VENDOR_ITEM_REGULAR),
+		list("Welding Goggles", 5, /obj/item/clothing/glasses/welding, null, VENDOR_ITEM_REGULAR),
 
 		list("POUCHES", 0, null, null, null),
 		list("Large Magazine Pouch", 10, /obj/item/storage/pouch/magazine/large, null, VENDOR_ITEM_REGULAR),

code/game/machinery/vending/vendor_types/squad_prep/squad_tl.dm

@@ -35,7 +35,9 @@ GLOBAL_LIST_INIT(cm_vending_gear_tl, list(
 		list("Motion Detector", 15, /obj/item/device/motiondetector, null, VENDOR_ITEM_RECOMMENDED),
 		list("Plastic Explosive", 10, /obj/item/explosive/plastic, null, VENDOR_ITEM_REGULAR),
 		list("Breaching Charge", 10, /obj/item/explosive/plastic/breaching_charge, null, VENDOR_ITEM_REGULAR),
+		list("Welding Visor", 5, /obj/item/device/helmet_visor/welding_visor, null, VENDOR_ITEM_REGULAR),
 		list("Medical Helmet Optic", 15, /obj/item/device/helmet_visor/medical, null, VENDOR_ITEM_REGULAR),
+		list("Welding Goggles", 5, /obj/item/clothing/glasses/welding, null, VENDOR_ITEM_REGULAR),
 		list("M2 Night Vision Goggles", 30, /obj/item/prop/helmetgarb/helmet_nvg, null, VENDOR_ITEM_RECOMMENDED),
 		list("Roller Bed", 5, /obj/item/roller, null, VENDOR_ITEM_REGULAR),
 		list("Fulton Device Stack", 5, /obj/item/stack/fulton, null, VENDOR_ITEM_REGULAR),
@@ -44,7 +46,6 @@ GLOBAL_LIST_INIT(cm_vending_gear_tl, list(
 		list("Machete Pouch (Full)", 15, /obj/item/storage/pouch/machete/full, null, VENDOR_ITEM_REGULAR),
 		list("Fire Extinguisher (Portable)", 5, /obj/item/tool/extinguisher/mini, null, VENDOR_ITEM_REGULAR),
 		list("Whistle", 5, /obj/item/device/whistle, null, VENDOR_ITEM_REGULAR),
-		list("Welding Goggles", 5, /obj/item/clothing/glasses/welding, null, VENDOR_ITEM_REGULAR),
 		list("Powerloader Certification", 45, /obj/item/pamphlet/skill/powerloader, null, VENDOR_ITEM_REGULAR),
 		list("Insulated Gloves", 3, /obj/item/clothing/gloves/yellow, null, VENDOR_ITEM_REGULAR),
 

code/modules/clothing/head/helmet.dm

@@ -761,16 +761,17 @@ GLOBAL_LIST_INIT(allowed_helmet_items, list(
 
 /obj/item/clothing/head/helmet/marine/rto
 	name = "\improper M12 pattern dust helmet"
-	desc = "An experimental brain-bucket. A dust ruffle hangs from back instead of the standard lobster shell design. Moderately better at deflecting blunt objects at the cost of humiliation. But who will be laughing at the memorial? Not you, you'll be busy getting medals for your fantastic leadership."
+	desc = "An experimental brain-bucket. A dust ruffle hangs from back instead of the standard lobster shell design. Moderately better at deflecting blunt objects at the cost of humiliation, can also hold a second visor optic. But who will be laughing at the memorial? Not you, you'll be busy getting medals for your fantastic leadership."
 	icon_state = "io"
 	item_state = "io"
 	armor_melee = CLOTHING_ARMOR_MEDIUMHIGH
 	armor_bio = CLOTHING_ARMOR_MEDIUMHIGH
 	specialty = "M12 pattern"
+	max_inserted_visors = 2
 
 /obj/item/clothing/head/helmet/marine/rto/intel
 	name = "\improper XM12 pattern intelligence helmet"
-	desc = "An experimental brain-bucket. A dust ruffle hangs from back. Moderately better at deflecting blunt objects at the cost of humiliation. But who will be laughing at the memorial? Not you, you'll be busy getting medals for your intel work."
+	desc = "An experimental brain-bucket. A dust ruffle hangs from back. Moderately better at deflecting blunt objects at the cost of humiliation, can also hold a second visor optic. But who will be laughing at the memorial? Not you, you'll be busy getting medals for your intel work."
 	specialty = "XM12 pattern intel"
 
 /obj/item/clothing/head/helmet/marine/specialist