Adds an universal object health system. (#21266)

https://www.youtube.com/watch?v=ZpUYjpKg9KY

As per title. The goal is to add health to most objects in the game and
thus allow them to be dynamically destructible, while also avoiding
shitcode like each structure having its own snowflake health update
proc.

---------

Signed-off-by: Matt Atlas <mattiathebest2000@hotmail.it>
Co-authored-by: Matt Atlas <liermattia@gmail.com>
Co-authored-by: SleepyGemmy <99297919+SleepyGemmy@users.noreply.github.com>

code/modules/modular_computers/computers/modular_computer/interaction.dm

@@ -311,14 +311,15 @@
 			to_chat(user, SPAN_WARNING("\The [attacking_item] is off."))
 			return TRUE
 
-		if(!damage)
+		if(health >= maxhealth)
 			to_chat(user, SPAN_WARNING("\The [src] does not require repairs."))
 			return TRUE
 
 		to_chat(user, SPAN_NOTICE("You begin repairing the damage to \the [src]..."))
 		playsound(get_turf(src), 'sound/items/Welder.ogg', 100, 1)
+		var/damage = maxhealth - health
 		if(WT.use(round(damage / 75)) && do_after(user, damage / 10, src, DO_REPAIR_CONSTRUCT))
-			damage = 0
+			health = maxhealth
 			to_chat(user, SPAN_NOTICE("You fully repair \the [src]."))
 		update_icon()
 		return TRUE
@@ -354,6 +355,15 @@
 		if(do_after(user, 1 SECONDS))
 			visible_message(SPAN_NOTICE("[user] slots \the [access_cable] into \the [src]."))
 			universal_port.insert_cable(access_cable, user)
+
+	if(user?.a_intent == I_HURT && maxhealth)
+		user.do_attack_animation(src)
+		user.setClickCooldown(DEFAULT_ATTACK_COOLDOWN)
+		visible_message(SPAN_DANGER("[user] [pick(attacking_item.attack_verb)] \the [src]!"))
+		add_damage(attacking_item.force, attacking_item.damage_flags(), attacking_item.damtype, attacking_item.armor_penetration, attacking_item)
+		playsound(user, 'sound/effects/metalhit.ogg', attacking_item.get_clamped_volume())
+		return TRUE
+
 	return ..()
 
 /obj/item/modular_computer/mouse_drop_dragged(atom/over, mob/user, src_location, over_location, params)