Fixes Xeno Name preference requring a reconnect to apply (#4660)

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# About the pull request

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See #4436 for an indepth description of the issue - basically Xeno name
is cached on client and updating preferences won't update it without a
reconnect (and the lobby screen even baits you thinking it does by
displaying pref not client's)

# Explain why it's good for the game

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Less confusion

Fixes #4436 

# Testing Photographs and Procedure
<!-- Include any screenshots/videos/debugging steps of the modified code
functioning successfully, ideally including edge cases. -->
Basic testing performed in the form of:
   Changing Xeno Name
   Launching game, observing
   Spawning a Xeno and possessing it
And observing which xeno name is present.


# Changelog

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:cl:
fix: Xeno Name preference does not require a reconnection to apply
anymore. It still won't change your current Xenomorph's name however.
/:cl:

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code/modules/client/client_procs.dm

@@ -330,13 +330,8 @@ GLOBAL_LIST_INIT(whitelisted_client_procs, list(
 	prefs.last_ip = address //these are gonna be used for banning
 	prefs.last_id = computer_id //these are gonna be used for banning
 	fps = prefs.fps
-	xeno_prefix = prefs.xeno_prefix
-	xeno_postfix = prefs.xeno_postfix
-	xeno_name_ban = prefs.xeno_name_ban
-	if(!xeno_prefix || xeno_name_ban)
-		xeno_prefix = "XX"
-	if(!xeno_postfix || xeno_name_ban)
-		xeno_postfix = ""
+
+	load_xeno_name()
 
 	human_name_ban = prefs.human_name_ban
 
@@ -790,3 +785,12 @@ GLOBAL_LIST_INIT(whitelisted_client_procs, list(
 	if(admin_holder)
 		admin_holder.particle_test = new /datum/particle_editor(in_atom)
 		admin_holder.particle_test.tgui_interact(mob)
+
+/client/proc/load_xeno_name()
+	xeno_prefix = prefs.xeno_prefix
+	xeno_postfix = prefs.xeno_postfix
+	xeno_name_ban = prefs.xeno_name_ban
+	if(!xeno_prefix || xeno_name_ban)
+		xeno_prefix = "XX"
+	if(!xeno_postfix || xeno_name_ban)
+		xeno_postfix = ""

code/modules/client/preferences.dm

@@ -1409,6 +1409,7 @@ var/const/MAX_SAVE_SLOTS = 10
 
 					if(length(new_xeno_prefix)==0)
 						xeno_prefix = "XX"
+						owner.load_xeno_name()
 					else
 						var/all_ok = TRUE
 						for(var/i=1, i<=length(new_xeno_prefix), i++)
@@ -1420,6 +1421,7 @@ var/const/MAX_SAVE_SLOTS = 10
 									all_ok = FALSE //everything else - won't
 						if(all_ok)
 							xeno_prefix = new_xeno_prefix
+							owner.load_xeno_name()
 						else
 							to_chat(user, "<font color='red'>Invalid Xeno Prefix. Your Prefix can contain either single letter or two letters.</font>")
 
@@ -1444,6 +1446,7 @@ var/const/MAX_SAVE_SLOTS = 10
 						return
 					else if(length(new_xeno_postfix)==0)
 						xeno_postfix = ""
+						owner.load_xeno_name()
 					else
 						var/all_ok = TRUE
 						var/first_char = TRUE
@@ -1469,6 +1472,7 @@ var/const/MAX_SAVE_SLOTS = 10
 							first_char = FALSE
 						if(all_ok)
 							xeno_postfix = new_xeno_postfix
+							owner.load_xeno_name()
 						else
 							to_chat(user, "<font color='red'>Invalid Xeno Postfix. Your Postfix can contain single letter and an optional digit after it.</font>")
 

code/modules/mob/new_player/new_player.dm

@@ -34,8 +34,8 @@
 		return
 
 	var/tempnumber = rand(1, 999)
-	var/postfix_text = (client.prefs && client.prefs.xeno_postfix) ? ("-"+client.prefs.xeno_postfix) : ""
-	var/prefix_text = (client.prefs && client.prefs.xeno_prefix) ? client.prefs.xeno_prefix : "XX"
+	var/postfix_text = (client.xeno_postfix) ? ("-"+client.xeno_postfix) : ""
+	var/prefix_text = (client.xeno_prefix) ? client.xeno_prefix : "XX"
 	var/xeno_text = "[prefix_text]-[tempnumber][postfix_text]"
 	var/round_start = !SSticker || !SSticker.mode || SSticker.current_state <= GAME_STATE_PREGAME