Fixes tempbody taking aghosted bodies (#95996)

## About The Pull Request

If you're an adminghosted body, you will no longer be sent back to your
corpse afterwards. The Mind will still move over, but you wont
immediately re-enter your body.

Just as an example, an Admin is aghosted on Centcom after testing some
stuff, plays a round of Mafia, then is suddenly back in their body in
Centcom.

Also fixes temp body not working for Mafia (due to the corpse locking)

## Why It's Good For The Game

You're going to the THUNDERDOME.

## Changelog

🆑
fix: Mafia players now get sent back to their bodies again post-game.
admin: Admin players aren't forcefully put back into aghosted bodies
after using a temporary body spawner.
/🆑

code/datums/components/temporary_body.dm

@@ -79,7 +79,7 @@
 	SIGNAL_HANDLER
 
 	var/mob/new_body = parent
-	var/mob/dead/observer/ghost = new_body.get_ghost() || new_body.ghostize()
+	var/mob/dead/observer/ghost = new_body.get_ghost() || new_body.ghostize(forced = TRUE)
 	if(QDELETED(ghost))
 		stack_trace("[src] belonging to [parent] was completely unable to find a ghost to put back into a body!")
 		qdel(src) // i guess this is useless now
@@ -90,7 +90,7 @@
 		if(old_mind.current != old_body)
 			stack_trace("Temporary body returning mind to old body, but the mind's current body doesn't match the old body!")
 			old_mind.set_current(old_body)
-		if(old_body.stat != DEAD)
+		if(old_body.stat != DEAD && !IS_FAKE_KEY(old_body.key))
 			ghost.reenter_corpse()
 
 	qdel(src) // we're done here

code/datums/mind/_mind.dm

@@ -472,6 +472,7 @@
 			if(G.can_reenter_corpse || even_if_they_cant_reenter)
 				return G
 			break
+	return null
 
 /datum/mind/proc/grab_ghost(force)
 	var/mob/dead/observer/G = get_ghost(even_if_they_cant_reenter = force)

code/modules/antagonists/changeling/powers/absorb.dm

@@ -227,9 +227,9 @@
 		return
 	ghostize(TRUE)
 
-/mob/eye/imaginary_friend/hivemind/ghostize(can_reenter_corpse, admin_ghost)
+/mob/eye/imaginary_friend/hivemind/ghostize(can_reenter_corpse, forced)
 	. = ..()
-	if(admin_ghost)
+	if(forced)
 		return
 
 	alert_hivemind("You sense the presence of [real_name] disappear from the hivemind.")

code/modules/mob/dead/observer/observer.dm

@@ -254,18 +254,22 @@ GLOBAL_VAR_INIT(observer_default_invisibility, INVISIBILITY_OBSERVER)
 		lum = max(read_color[3], 80)
 	return rgb(read_color[1], sat, lum, space = COLORSPACE_HSL)
 
-/*
-Transfer_mind is there to check if mob is being deleted/not going to have a body.
-Works together with spawning an observer, noted above.
-*/
-
-/mob/proc/ghostize(can_reenter_corpse = TRUE, admin_ghost = FALSE)
+/**
+ * # Ghostize
+ *
+ * Creates a /mob/dead/observer and moves the player's key into it (among other handling for player->observer)
+ * Ignores things like adminghosts and corpselocked (ethereal) players.
+ * Args:
+ * can_reenter_corse: Whether the new Ghost will be able to click "Re-enter body", TRUE by default.
+ * forced: Whether we are forcing this player to be ghosted, ignoring things like corpselocking, FALSE by default.
+ */
+/mob/proc/ghostize(can_reenter_corpse = TRUE, forced = FALSE)
 	if(!key)
 		return
 	if(IS_FAKE_KEY(key)) // Skip aghosts.
 		return
 
-	if(HAS_TRAIT(src, TRAIT_CORPSELOCKED) && !admin_ghost)
+	if(HAS_TRAIT(src, TRAIT_CORPSELOCKED) && !forced)
 		if(can_reenter_corpse) //If you can re-enter the corpse you can't leave when corpselocked
 			return
 		if(ishuman(usr)) //following code only applies to those capable of having an ethereal heart, ie humans
@@ -293,7 +297,7 @@ Works together with spawning an observer, noted above.
 	SEND_SIGNAL(src, COMSIG_MOB_GHOSTIZED)
 	return ghost
 
-/mob/living/ghostize(can_reenter_corpse = TRUE)
+/mob/living/ghostize(can_reenter_corpse = TRUE, forced = FALSE)
 	. = ..()
 	if(. && can_reenter_corpse)
 		var/mob/dead/observer/ghost = .