Fixes jousting bypassing pacifism + Some signal doc (#82986)

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## About The Pull Request

Closes https://github.com/tgstation/tgstation/issues/82983

Title.

Jousting now uses a shiny new post-attack signal, only sent if the
attack is actually executed.

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## Why It's Good For The Game

bgus bad

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🆑 nikothedude
fix: Jousting no longer bypasses pacifism
/🆑

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code/__DEFINES/dcs/signals/signals_object.dm

@@ -448,7 +448,10 @@
 	/// Prevents click from happening.
 	#define COMPONENT_CANCEL_EQUIPMENT_CLICK (1<<0)
 
+///from base of /obj/item/attack(): (mob/living, mob/living, params)
 #define COMSIG_ITEM_ATTACK "item_attack"
+///from base of /obj/item/attack(): (mob/living, mob/living, params)
+#define COMSIG_ITEM_POST_ATTACK "item_post_attack" // called only if the attack was executed
 ///from base of obj/item/attack_self(): (/mob)
 #define COMSIG_ITEM_ATTACK_SELF "item_attack_self"
 //from base of obj/item/attack_self_secondary(): (/mob)

code/_onclick/item_attack.dm

@@ -236,6 +236,8 @@
 	user.do_attack_animation(target_mob)
 	target_mob.attacked_by(src, user)
 
+	SEND_SIGNAL(src, COMSIG_ITEM_POST_ATTACK, target_mob, user, params)
+
 	log_combat(user, target_mob, "attacked", src.name, "(COMBAT MODE: [uppertext(user.combat_mode)]) (DAMTYPE: [uppertext(damtype)])")
 	add_fingerprint(user)
 

code/datums/components/jousting.dm

@@ -44,7 +44,7 @@
 	RegisterSignal(parent, COMSIG_ATOM_EXAMINE, PROC_REF(on_examine))
 	RegisterSignal(parent, COMSIG_ITEM_EQUIPPED, PROC_REF(on_equip))
 	RegisterSignal(parent, COMSIG_ITEM_DROPPED, PROC_REF(on_drop))
-	RegisterSignal(parent, COMSIG_ITEM_ATTACK, PROC_REF(on_attack))
+	RegisterSignal(parent, COMSIG_ITEM_POST_ATTACK, PROC_REF(on_successful_attack))
 	RegisterSignal(parent, COMSIG_TRANSFORMING_ON_TRANSFORM, PROC_REF(on_transform))
 
 /datum/component/jousting/UnregisterFromParent()
@@ -53,7 +53,7 @@
 		COMSIG_ATOM_EXAMINE,
 		COMSIG_ITEM_EQUIPPED,
 		COMSIG_ITEM_DROPPED,
-		COMSIG_ITEM_ATTACK,
+		COMSIG_ITEM_POST_ATTACK,
 		COMSIG_TRANSFORMING_ON_TRANSFORM,
 	))
 
@@ -94,7 +94,7 @@
  * We deduct the minimum tile charge from the current tile charge to get what will actually be buffed
  * So your charge will only get benefits from each extra tile after the minimum (and before the maximum).
  */
-/datum/component/jousting/proc/on_attack(datum/source, mob/living/target, mob/user)
+/datum/component/jousting/proc/on_successful_attack(datum/source, mob/living/target, mob/user)
 	SIGNAL_HANDLER
 	if(user != current_holder || !user.buckled)
 		return