Ensures some ling ability icon always update correctly, Fixes a potential input stall in Revival Stasis (#73616)

## About The Pull Request

- For Fleshmend, on apply kinda happens before alerts are made, so using
Fleshmend when you're on fire wouldn't make the alert the "you're on
fire" alert.

- For Revival Stasis, I think I just missed an update call? Which made
it not update on occasion.
- I also patched a potential issue with input stalling on Revival Stasis
while here.

## Changelog

🆑 Melbert
fix: Using Fleshmend while on fire gives the "on fire" fleshmend icon. 
fix: Using Revival stasis more accurately updates the icon where
relevant
fix: Fixes a potential input stall with revival stasis
/🆑

code/datums/status_effects/buffs.dm

@@ -158,6 +158,13 @@
 	RegisterSignal(owner, COMSIG_LIVING_IGNITED, PROC_REF(on_ignited))
 	RegisterSignal(owner, COMSIG_LIVING_EXTINGUISHED, PROC_REF(on_extinguished))
 
+/datum/status_effect/fleshmend/on_creation(mob/living/new_owner, ...)
+	. = ..()
+	if(!. || !owner || !linked_alert)
+		return
+	if(owner.on_fire)
+		linked_alert.icon_state = "fleshmend_fire"
+
 /datum/status_effect/fleshmend/on_remove()
 	UnregisterSignal(owner, list(COMSIG_LIVING_IGNITED, COMSIG_LIVING_EXTINGUISHED))