[DNM][DNM][WIP] Projectile backend code port and update

Ports#54924,  #65061, #59804 from /tg.
adds auxiliary code from /tg to make code work.

code/datums/components/mirv.dm

@@ -38,5 +38,5 @@
 			P.range = override_projectile_range
 		P.preparePixelProjectile(shootat_turf, target)
 		P.firer = firer // don't hit ourself that would be really annoying
-		P.permutated += target // don't hit the target we hit already with the flak
+		P.impacted = list(target = TRUE) // don't hit the target we hit already with the flak
 		P.fire()

code/datums/components/pellet_cloud.dm

@@ -242,7 +242,7 @@
 	P.original = target
 	P.fired_from = parent
 	P.firer = parent // don't hit ourself that would be really annoying
-	P.permutated += parent // don't hit the target we hit already with the flak
+	P.impacted = list(parent = TRUE) // don't hit the target we hit already with the flak
 	P.suppressed = SUPPRESSED_VERY // set the projectiles to make no message so we can do our own aggregate message
 	P.preparePixelProjectile(target, parent)
 	RegisterSignal(P, COMSIG_PROJECTILE_SELF_ON_HIT, .proc/pellet_hit)