Adds in missing stub signals

code/game/atoms_movable.dm

@@ -214,6 +214,7 @@
 //called when src is thrown into hit_atom
 /atom/movable/proc/throw_impact(atom/hit_atom, throwingdatum)
 	set waitfor = 0
+	SEND_SIGNAL(src, COMSIG_MOVABLE_IMPACT, hit_atom, throwingdatum)
 	if(!QDELETED(hit_atom))
 		return hit_atom.hitby(src)
 

code/game/objects/items.dm

@@ -325,6 +325,7 @@ var/global/image/fire_overlay = image("icon" = 'icons/goonstation/effects/fire.d
 		A.Remove(user)
 	if(flags & DROPDEL)
 		qdel(src)
+	SEND_SIGNAL(src, COMSIG_ITEM_DROPPED,user)
 
 // called just as an item is picked up (loc is not yet changed)
 /obj/item/proc/pickup(mob/user)
@@ -352,6 +353,7 @@ var/global/image/fire_overlay = image("icon" = 'icons/goonstation/effects/fire.d
 // for items that can be placed in multiple slots
 // note this isn't called during the initial dressing of a player
 /obj/item/proc/equipped(var/mob/user, var/slot)
+	SEND_SIGNAL(src, COMSIG_ITEM_EQUIPPED, user, slot)
 	for(var/X in actions)
 		var/datum/action/A = X
 		if(item_action_slot_check(slot, user)) //some items only give their actions buttons when in a specific slot.

code/modules/clothing/clothing.dm

@@ -411,6 +411,7 @@ BLIND     // can't see anything
 		..()
 
 /obj/item/clothing/shoes/proc/step_action(var/mob/living/carbon/human/H) //squeek squeek
+	SEND_SIGNAL(src, COMSIG_SHOES_STEP_ACTION)
 	if(shoe_sound)
 		var/turf/T = get_turf(H)