More Mech Damage Feedback (#22118)

This PR adds some new "Damage Feedback" interactions to mechs, which I'm
adding in response to what I think is player perception of mechs being
invincible. Previously mech manipulators and torsos had no actual
mechanics for damage states, and having 0 damage on a mechs arms was
functionally the same thing as having 100 damage, so long as the arm
wasn't completely destroyed.

This PR changes that by making it so that mech manipulators have a
chance to fail (loudly and visibly) on use with a probability that
varies based on how much damage the arms have taken. Additionally,
there's also now a mechanic for mech ejections and hatch opening to fail
if the torso has taken sufficient damage, with chances that also vary
based on how much damage said torso has taken. In both cases, the mech
plays audible and visual effects to indicate to the players involved
that it is being hindered by damage.


https://github.com/user-attachments/assets/934e4561-1fda-4c47-9770-438960834aa9

Yes this does mean that you can smash someone's hatch closed, to a point
you'll need a welder to get them out.

<img width="772" height="181" alt="image"
src="https://github.com/user-attachments/assets/75f98060-7c4c-468b-bd31-e6c4ec4c0be2"
/>

code/modules/heavy_vehicle/interface/screen_objects.dm

@@ -211,6 +211,8 @@
 /atom/movable/screen/mecha/toggle/air/toggled()
 	toggled = !toggled
 	owner.use_air = toggled
+	if (owner.use_air)
+		playsound(owner.loc, 'sound/effects/internals.ogg', 75, 1)
 	var/main_color = owner.use_air ? "#d1d1d1" : "#525252"
 	maptext = "<span style=\"font-family: 'Small Fonts'; color: [main_color]; -dm-text-outline: 1 #242424; font-size: 6px;\">AIR</span>"
 	notify_user(usr, SPAN_NOTICE("Auxiliary atmospheric system [owner.use_air ? "enabled" : "disabled"]."))
@@ -286,6 +288,7 @@
 		maptext_y = 11
 		maptext_x = 5
 	notify_user(usr, SPAN_NOTICE("The [owner.body.hatch_descriptor] is [owner.hatch_locked ? "now" : "no longer" ] locked."))
+	playsound(owner.loc, 'sound/effects/magnetclamp.ogg', 100, 1)
 
 /atom/movable/screen/mecha/toggle/hatch_open
 	name = "open or close hatch"
@@ -298,15 +301,29 @@
 	maptext_x = owner.hatch_closed ? 4 : 3
 
 /atom/movable/screen/mecha/toggle/hatch_open/toggled(var/notify_user = TRUE)
+	var/obj/item/mech_component/chassis/body = owner.body
+	if(!body) // Edge case for the mech SOMEHOW not having a body. Players shouldn't ever see this. A mech without a body should be in the process of exploding.
+		notify_user(usr, SPAN_WARNING("What hatch? There's nothing left to open. If you're seeing this, please submit a bug report to our github issue tracker and tell us how!"))
+		return FALSE
+
 	if(owner.hatch_locked && owner.hatch_closed)
 		notify_user(usr, SPAN_WARNING("You cannot open the hatch while it is locked."))
-		return
+		return FALSE
+
+	if(owner.hatch_closed && body.total_damage > 1 && prob((body.total_damage / body.max_damage) * body.ejection_fail_chance))
+		to_chat(usr, SPAN_WARNING("You pull the hatch release. The hatch bolts hiss and clang with a deafening screech, but the hatch fails to open!"))
+		spark(owner, 6, GLOB.alldirs)
+		playsound(owner.loc, 'sound/effects/metalhit.ogg', 75, 1)
+		return FALSE
+
 	toggled = !toggled
 	owner.hatch_closed = toggled
+	playsound(owner.loc, owner.hatch_closed ? 'sound/effects/metal_close.ogg' : 'sound/effects/air_seal.ogg', 75, 1)
 	if(notify_user)
 		notify_user(usr, SPAN_NOTICE("The [owner.body.hatch_descriptor] is now [owner.hatch_closed ? "closed" : "open" ]."))
 	update_icon()
 	owner.update_icon()
+	return TRUE
 
 // This is basically just a holder for the updates the mech does.
 /atom/movable/screen/mecha/health