Refactors armor into dedicated subtypes (#71986)

## About The Pull Request

See title.
## Why It's Good For The Game

Code is cleaner, and more readable/intuitive
Technically closes
https://github.com/tgstation/dev-cycles-initiative/issues/8
## Changelog
🆑
refactor: armor, from the ground up basically
/🆑

Co-authored-by: Mothblocks <35135081+Mothblocks@users.noreply.github.com>

code/game/objects/structures/displaycase.dm

@@ -6,7 +6,7 @@
 	density = TRUE
 	anchored = TRUE
 	resistance_flags = ACID_PROOF
-	armor = list(MELEE = 30, BULLET = 0, LASER = 0, ENERGY = 0, BOMB = 10, BIO = 0, FIRE = 70, ACID = 100)
+	armor_type = /datum/armor/structure_displaycase
 	max_integrity = 200
 	integrity_failure = 0.25
 	///The showpiece item inside the case
@@ -29,6 +29,12 @@
 	///Used for subtypes that have a UI in them. The examine on click while adjecent will not fire, as we already get a popup
 	var/autoexamine_while_closed = TRUE
 
+/datum/armor/structure_displaycase
+	melee = 30
+	bomb = 10
+	fire = 70
+	acid = 100
+
 /obj/structure/displaycase/Initialize(mapload)
 	. = ..()
 	if(start_showpiece_type)
@@ -227,6 +233,12 @@
 	var/obj/item/electronics/airlock/electronics
 
 
+/datum/armor/structure_displaycase
+	melee = 30
+	bomb = 10
+	fire = 70
+	acid = 100
+
 /obj/structure/displaycase_chassis/attackby(obj/item/I, mob/user, params)
 	if(I.tool_behaviour == TOOL_WRENCH) //The player can only deconstruct the wooden frame
 		to_chat(user, span_notice("You start disassembling [src]..."))
@@ -307,6 +319,12 @@
 	///the trophy message
 	var/trophy_message = ""
 
+/datum/armor/structure_displaycase
+	melee = 30
+	bomb = 10
+	fire = 70
+	acid = 100
+
 /obj/structure/displaycase/trophy/Initialize(mapload)
 	. = ..()
 	GLOB.trophy_cases += src
@@ -423,6 +441,12 @@
 /obj/item/showpiece_dummy
 	name = "holographic replica"
 
+/datum/armor/structure_displaycase
+	melee = 30
+	bomb = 10
+	fire = 70
+	acid = 100
+
 /obj/item/showpiece_dummy/Initialize(mapload, path)
 	. = ..()
 	var/obj/item/item_path = path
@@ -448,6 +472,12 @@
 	///The Account which will receive payment for purchases. Set by the first ID to swipe the tray.
 	var/datum/bank_account/payments_acc = null
 
+/datum/armor/structure_displaycase
+	melee = 30
+	bomb = 10
+	fire = 70
+	acid = 100
+
 /obj/structure/displaycase/forsale/update_icon_state()
 	icon_state = "[initial(icon_state)][broken ? "_broken" : (open ? "_open" : (!showpiece ? "_empty" : null))]"
 	return ..()