Fixes chasm jaunters not working while you're buckled to a mob or an object (#92693)

## About The Pull Request

Now all mobs are unbuckled from falling objects and dropped
individually, similarly to how lava functions. Also updated jaunters to
be comsig-based rather than chasms snowflake checking for jaunters in
belt slots.
Closes #92663

code/modules/mining/equipment/wormhole_jaunter.dm

@@ -50,7 +50,7 @@
 			to_chat(user, span_notice("\The [src] found no beacons in the world to anchor a wormhole to."))
 		else
 			visible_message(span_notice("\The [src] found no beacons in the world to anchor a wormhole to!"))
-		return TRUE // used for chasm code
+		return FALSE
 
 	var/list/destinations = get_destinations()
 	var/chosen_beacon = pick(destinations)
@@ -62,7 +62,7 @@
 		try_move_adjacent(tunnel)
 
 	qdel(src)
-	return FALSE // used for chasm code
+	return TRUE
 
 /obj/item/wormhole_jaunter/emp_act(power)
 	. = ..()
@@ -77,20 +77,32 @@
 
 	var/mob/M = loc
 	if(istype(M) && triggered)
-		M.visible_message(span_warning("Your [src.name] overloads and activates!"))
+		M.visible_message(span_userdanger("Your [src.name] overloads and activates!"))
 		SSblackbox.record_feedback("tally", "jaunter", 1, "EMP") // EMP accidental activation
 		activate(M, FALSE, TRUE)
 	else if(triggered)
 		visible_message(span_warning("\The [src] overloads and activates!"))
 		activate()
 
-/obj/item/wormhole_jaunter/proc/chasm_react(mob/user)
-	var/fall_into_chasm = activate(user, FALSE, TRUE)
+/obj/item/wormhole_jaunter/equipped(mob/user, slot, initial)
+	. = ..()
+	if (slot & ITEM_SLOT_BELT)
+		RegisterSignal(user, COMSIG_MOVABLE_CHASM_DROPPED, PROC_REF(chasm_react))
 
-	if(!fall_into_chasm)
-		to_chat(user, span_notice("Your [src.name] activates, saving you from the chasm!"))
-		SSblackbox.record_feedback("tally", "jaunter", 1, "Chasm") // chasm automatic activation
-	return fall_into_chasm
+/obj/item/wormhole_jaunter/dropped(mob/user, silent)
+	. = ..()
+	UnregisterSignal(user, COMSIG_MOVABLE_CHASM_DROPPED)
+
+/obj/item/wormhole_jaunter/proc/chasm_react(mob/living/user, turf/chasm)
+	SIGNAL_HANDLER
+
+	if(!activate(user, FALSE, TRUE))
+		return
+
+	to_chat(user, span_userdanger("Your [src] activates, saving you from \the [chasm]!"))
+	chasm.visible_message(span_boldwarning("[user] falls into \the [chasm]!")) // To freak out any bystanders
+	SSblackbox.record_feedback("tally", "jaunter", 1, "Chasm") // Chasm automatic activation
+	return COMPONENT_NO_CHASM_DROP
 
 //jaunter tunnel
 /obj/effect/portal/jaunt_tunnel