Some VChat Tweaks

- Chat remains between client reconnects if your client didn't close (so things like using the reconnect button, or autoreconnects at round end when that feels like working)
- The client doesn't send pings to the server, the server sends pings to the client. This fixes AFK measurements for AFK kick purposes.
- Turn latency indicator into a green/red indicator to show if you're connected, and when clicked will perform a one-time ping (and block doing it again for 10 seconds). It will display '?ms' if it never got a reply, or '999ms' if it did, but it was over 1s.

code/modules/vchat/vchat_client.dm

@@ -46,7 +46,6 @@ GLOBAL_DATUM_INIT(iconCache, /savefile, new("data/iconCache.sav")) //Cache of ic
 	. = ..()
 
 	owner = C
-	update_vis()
 
 /datum/chatOutput/Destroy()
 	owner = null
@@ -78,14 +77,20 @@ GLOBAL_DATUM_INIT(iconCache, /savefile, new("data/iconCache.sav")) //Cache of ic
 		become_broken()
 		return FALSE
 
+	//Could be loaded from a previous round, are you still there?
+	if(winget(owner,"outputwindow.htmloutput","is-visible") == "true") //Winget returns strings
+		send_event(event = list("evttype" = "availability"))
+		sleep(3 SECONDS)
+
 	if(!owner) // In case the client vanishes before winexists returns
 		qdel(src)
 		return FALSE
 
-	if(!resources_sent)
-		send_resources()
-
-	load()
+	if(!loaded)
+		update_vis()
+		if(!resources_sent)
+			send_resources()
+		load()
 
 	return TRUE
 
@@ -115,7 +120,7 @@ GLOBAL_DATUM_INIT(iconCache, /savefile, new("data/iconCache.sav")) //Cache of ic
 	owner.chatOutputLoadedAt = world.time
 	
 	//update_vis() //It does it's own winsets
-
+	ping_cycle()
 	send_playerinfo()
 	load_database()
 	
@@ -163,9 +168,23 @@ GLOBAL_DATUM_INIT(iconCache, /savefile, new("data/iconCache.sav")) //Cache of ic
 /datum/chatOutput/proc/send_event(var/event, var/client/C = owner)
 	C << output(jsEncode(event), "htmloutput:get_event")
 
+//Looping sleeping proc that just pings the client and dies when we die
+/datum/chatOutput/proc/ping_cycle()
+	set waitfor = FALSE
+	while(!QDELING(src))
+		if(!owner)
+			qdel(src)
+			return
+		send_event(event = keep_alive())
+		sleep(20 SECONDS) //Make sure this makes sense with what the js client is expecting
+
 //Just produces a message for using in keepalives from the server to the client
-/datum/chatOutput/proc/keepalive()
-	return list("evttype" = "keepalive_server")
+/datum/chatOutput/proc/keep_alive()
+	return list("evttype" = "keepalive")
+
+//A response to a latency check from the client
+/datum/chatOutput/proc/latency_check()
+	return list("evttype" = "pong")
 
 //Redirected from client/Topic when the user clicks a link that pertains directly to the chat (when src == "chat")
 /datum/chatOutput/Topic(var/href, var/list/href_list)
@@ -197,8 +216,8 @@ GLOBAL_DATUM_INIT(iconCache, /savefile, new("data/iconCache.sav")) //Cache of ic
 			CRASH("Tried to send a message to [owner.ckey] chatOutput before it was ready!")
 		if("done_loading")
 			data = done_loading(arglist(params))
-		if("keepalive_client")
-			data = keepalive(arglist(params))
+		if("ping")
+			data = latency_check(arglist(params))
 		if("ident")
 			data = bancheck(arglist(params))
 		if("unloading")