Added screen alerts (#22051)

Ports screen alerts from CM13. This enables an immediate reference to
whether you are cuffed or buckled. It also provides an easy way to get
out of said situation by simply clicking on the alert.

<img width="430" height="454" alt="image"
src="https://github.com/user-attachments/assets/0c20abf2-0901-49e0-ac29-492ba7c6dbe5"
/>


### Asset Licenses
The following assets that **have not** been created by myself are
included in this PR:

| Path | Original Author | License |
| --- | --- | --- |
| icons/mob/screen_alert.dmi (buckle, succumb) | CM13Devs (CM-13) |
CC-BY-SA 3.0 |

code/modules/mob/living/carbon/alien/life.dm

@@ -148,11 +148,8 @@
 
 	if(environment.temperature > (T0C+66))
 		adjustFireLoss((environment.temperature - (T0C+66))/5) // Might be too high, check in testing.
-		if (fire) fire.icon_state = "fire2"
 		if(prob(20))
 			to_chat(src, SPAN_DANGER("You feel a searing heat!"))
-	else
-		if (fire) fire.icon_state = "fire0"
 
 /mob/living/carbon/alien/handle_fire(var/seconds_per_tick, var/datum/gas_mixture/environment)
 	if(..())

code/modules/mob/living/carbon/carbon.dm

@@ -376,23 +376,6 @@
 		return 1
 	return
 
-/mob/living/carbon/u_equip(obj/item/W as obj)
-	if(!W)	return 0
-
-	else if (W == handcuffed)
-		handcuffed = null
-		update_inv_handcuffed()
-		if(buckled_to && buckled_to.buckle_require_restraints)
-			buckled_to.unbuckle()
-
-	else if (W == legcuffed)
-		legcuffed = null
-		update_inv_legcuffed()
-	else
-		..()
-
-	return
-
 //			output for machines^	^^^^^^^output for people^^^^^^^^^
 
 /mob/living/carbon/verb/mob_sleep()

code/modules/mob/living/carbon/human/inventory.dm

@@ -215,12 +215,10 @@ This saves us from having to call add_fingerprint() any time something is put in
 		update_inv_back()
 	else if (W == handcuffed)
 		handcuffed = null
-		if(buckled_to && buckled_to.buckle_require_restraints)
-			buckled_to.unbuckle()
-		update_inv_handcuffed()
+		handcuff_update()
 	else if (W == legcuffed)
 		legcuffed = null
-		update_inv_legcuffed()
+		legcuff_update()
 	else if (W == r_hand)
 		r_hand = null
 		update_inv_r_hand()
@@ -265,11 +263,11 @@ This saves us from having to call add_fingerprint() any time something is put in
 			update_inv_wear_mask(redraw_mob)
 		if(slot_handcuffed)
 			src.handcuffed = W
-			update_inv_handcuffed(redraw_mob)
+			handcuff_update()
 		if(slot_legcuffed)
 			src.legcuffed = W
 			W.on_equipped(src, slot, assisted_equip)
-			update_inv_legcuffed(redraw_mob)
+			legcuff_update()
 		if(slot_l_hand)
 			src.l_hand = W
 			W.on_equipped(src, slot, assisted_equip)

code/modules/mob/living/carbon/human/life.dm

@@ -1062,12 +1062,6 @@
 			if (oxygen.icon_state != new_oxy)
 				oxygen.icon_state = new_oxy
 
-		if(fire)
-			//fire_alert is either 0 if no alert, 1 for cold and 2 for heat.
-			var/new_fire = fire_alert ? "fire[fire_alert]" : "fire0"
-			if (fire.icon_state != new_fire)
-				fire.icon_state = new_fire
-
 		if(bodytemp)
 			var/new_temp
 			if (!species)

code/modules/mob/living/carbon/human/update_icons.dm

@@ -1476,8 +1476,10 @@ There are several things that need to be remembered:
 
 	if(!on_fire)
 		set_light_on(FALSE)
+		clear_alert(ALERT_FIRE)
 	else
 		set_light_on(TRUE)
+		throw_alert(ALERT_FIRE, /atom/movable/screen/alert/fire)
 
 	var/image/fire_image_lower = on_fire ? image(species.onfire_overlay, "lower", layer = FIRE_LAYER_LOWER) : null
 	var/image/fire_image_upper = on_fire ? image(species.onfire_overlay, "upper", layer = FIRE_LAYER_UPPER) : null

code/modules/mob/living/carbon/inventory.dm

@@ -0,0 +1,33 @@
+/mob/living/carbon/proc/handcuff_update()
+	if(handcuffed)
+		drop_r_hand()
+		drop_l_hand()
+		stop_pulling()
+		throw_alert("Handcuffed", /atom/movable/screen/alert/restrained/handcuffed, new_master = handcuffed)
+	else
+		clear_alert("Handcuffed")
+		if(buckled_to && buckled_to.buckle_require_restraints)
+			buckled_to.unbuckle()
+	update_inv_handcuffed()
+
+/mob/living/carbon/proc/legcuff_update()
+	if(legcuffed)
+		throw_alert("Legcuffed", /atom/movable/screen/alert/restrained/legcuffed, new_master = legcuffed)
+	else
+		clear_alert("Legcuffed")
+	update_inv_legcuffed()
+
+/mob/living/carbon/u_equip(obj/item/W as obj)
+	if(!W)	return 0
+
+	else if (W == handcuffed)
+		handcuffed = null
+		handcuff_update()
+
+	else if (W == legcuffed)
+		legcuffed = null
+		legcuff_update()
+	else
+		..()
+
+	return

code/modules/mob/living/carbon/resist.dm

@@ -171,7 +171,7 @@
 
 		drop_from_inventory(legcuffed)
 		legcuffed = null
-		update_inv_legcuffed()
+		legcuff_update()
 
 /mob/living/carbon/proc/can_break_cuffs()
 	if((mutations & HULK))
@@ -206,9 +206,7 @@
 
 		qdel(handcuffed)
 		handcuffed = null
-		if(buckled_to)
-			buckled_to.unbuckle()
-		update_inv_handcuffed()
+		handcuff_update()
 
 /mob/living/carbon/proc/break_legcuffs()
 	to_chat(src, SPAN_WARNING("You attempt to break your legcuffs. (This will take around 5 seconds and you need to stand still)"))
@@ -227,7 +225,7 @@
 
 		qdel(legcuffed)
 		legcuffed = null
-		update_inv_legcuffed()
+		legcuff_update()
 
 /mob/living/carbon/human/can_break_cuffs()
 	if(species.can_shred(src,1))

code/modules/mob/living/silicon/robot/life.dm

@@ -332,6 +332,9 @@
 	if(on_fire)
 		AddOverlays(image("icon" = 'icons/mob/burning/burning_generic.dmi', "icon_state" = "upper"))
 		AddOverlays(image("icon" = 'icons/mob/burning/burning_generic.dmi', "icon_state" = "lower"))
+		throw_alert(ALERT_FIRE, /atom/movable/screen/alert/fire)
+	else
+		clear_alert(ALERT_FIRE)
 
 /mob/living/silicon/robot/fire_act(exposed_temperature, exposed_volume)
 	. = ..()

code/modules/mob/living/simple_animal/constructs/constructs/cult_construct.dm

@@ -135,10 +135,6 @@
 	. = ..()
 	if(.)
 		var/newstate
-		if(fire)
-			newstate = fire_alert ? "fire1" : "fire0"
-			if(fire.icon_state != newstate)
-				fire.icon_state = newstate
 
 		if(pullin)
 			newstate = pulling ? "pull1" : "pull0"

code/modules/mob/living/simple_animal/simple_animal.dm

@@ -1072,6 +1072,9 @@
 		AddOverlays(upper_fire_emissive)
 		AddOverlays(lower_fire_overlay)
 		AddOverlays(lower_fire_emissive)
+		throw_alert(ALERT_FIRE, /atom/movable/screen/alert/fire)
+	else
+		clear_alert(ALERT_FIRE)
 
 
 /mob/living/simple_animal/get_resist_power()

code/modules/mob/mob.dm

@@ -70,7 +70,6 @@
 	i_select = null
 	m_select = null
 	toxin = null
-	fire = null
 	bodytemp = null
 	healths = null
 	throw_icon = null

code/modules/mob/mob_defines.dm

@@ -37,7 +37,6 @@
 	var/atom/movable/screen/i_select = null
 	var/atom/movable/screen/m_select = null
 	var/atom/movable/screen/toxin = null
-	var/atom/movable/screen/fire = null
 	var/atom/movable/screen/bodytemp = null
 	var/atom/movable/screen/healths = null
 	var/atom/movable/screen/throw_icon = null
@@ -168,6 +167,8 @@
 	var/obj/item/storage/s_active = null//Carbon
 	var/obj/item/clothing/mask/wear_mask = null//Carbon
 
+	/// contains [/atom/movable/screen/alert only] // On /mob so clientless mobs will throw alerts properly
+	var/list/alerts = list()
 	var/list/screens = list()
 
 	var/seer = 0 //for cult//Carbon, probably Human