Fixes the Hive Status error when the Queen dies (#5316)

# About the pull request

Fixes the Hive Status window showing an error message when the Queen
dies.

For xeno players, the interface just closes.
For observing players, the interface will show 'The Hive has no Queen!'
where the queen's location was previously.
(The bug actually causing the error should be fixed too now)

(Note: I'm not quite sure what the `tgui-panel.bundle.css` diff is from,
but it kept modifying itself whenever I compiled so I figured it was
something related to this.)

# Explain why it's good for the game

Fixes #4330

# Testing Photographs and Procedure
<details>
<summary>Screenshots & Videos</summary>

**Testing queen spawn and death as the queen, as an observer, and as a
xeno:**


https://github.com/cmss13-devs/cmss13/assets/57483089/ba3b2960-d4ce-4be4-af6b-6daae2d10ac1

</details>


# Changelog
:cl:
fix: Fixed the Hive Status window showing an error message when the
Queen dies.
/:cl:

code/modules/mob/living/carbon/xenomorph/Xenomorph.dm

@@ -432,6 +432,9 @@
 	if(mob_size < MOB_SIZE_BIG)
 		mob_flags |= SQUEEZE_UNDER_VEHICLES
 
+	GLOB.living_xeno_list += src
+	GLOB.xeno_mob_list += src
+
 	// More setup stuff for names, abilities etc
 	update_icon_source()
 	generate_name()
@@ -453,9 +456,6 @@
 	//Begin SStracking
 	SStracking.start_tracking("hive_[src.hivenumber]", src)
 
-	GLOB.living_xeno_list += src
-	GLOB.xeno_mob_list += src
-
 	//WO GAMEMODE
 	if(SSticker?.mode?.hardcore)
 		hardcore = 1 //Prevents healing and queen evolution

code/modules/mob/living/carbon/xenomorph/hive_status.dm

@@ -422,28 +422,27 @@
 // The idea is that we sort this list, and use it as a "key" for all the other information (especially the nicknumber)
 // in the hive status UI. That way we can minimize the amount of sorts performed by only calling this when xenos are created/disposed
 /datum/hive_status/proc/get_xeno_keys()
-	var/list/xenos[totalXenos.len]
+	var/list/xenos = list()
 
-	var/index = 1
-	var/useless_slots = 0
 	for(var/mob/living/carbon/xenomorph/X in totalXenos)
 		if(should_block_game_interaction(X))
 			var/area/A = get_area(X)
 			if(!(A.flags_atom & AREA_ALLOW_XENO_JOIN))
-				useless_slots++
 				continue
 
-		// Insert without doing list merging
-		xenos[index++] = list(
+		if(!(X in GLOB.living_xeno_list))
+			continue
+
+		// This looks weird, but in DM adding List A to List B actually adds each item in List B to List A, not List B itself.
+		// Having a nested list like this sort of tricks it into adding the list instead.
+		// In this case this results in an array of different 'xeno' dictionaries, rather than just a dictionary.
+		xenos += list(list(
 			"nicknumber" = X.nicknumber,
 			"tier" = X.tier, // This one is only important for sorting
 			"is_leader" = (IS_XENO_LEADER(X)),
 			"is_queen" = istype(X.caste, /datum/caste_datum/queen),
 			"caste_type" = X.caste_type
-		)
-
-	// Clear nulls from the xenos list
-	xenos.len -= useless_slots
+		))
 
 	// Make it all nice and fancy by sorting the list before returning it
 	var/list/sorted_keys = sort_xeno_keys(xenos)

code/modules/mob/living/carbon/xenomorph/hive_status_ui.dm

@@ -123,6 +123,10 @@
 	if(isobserver(user))
 		return UI_INTERACTIVE
 
+	// If the Queen died or is otherwise missing.
+	if(!assoc_hive.living_xeno_queen)
+		return UI_CLOSE
+
 /datum/hive_status_ui/ui_data(mob/user)
 	. = list()
 	.["total_xenos"] = total_xenos
@@ -131,7 +135,9 @@
 	.["xeno_keys"] = xeno_keys
 	.["xeno_info"] = xeno_info
 	.["xeno_vitals"] = xeno_vitals
-	.["queen_location"] = get_area_name(assoc_hive.living_xeno_queen)
+	.["queen_location"] = null
+	if(assoc_hive.living_xeno_queen)
+		.["queen_location"] = get_area_name(assoc_hive.living_xeno_queen)
 	.["hive_location"] = hive_location
 	.["burrowed_larva"] = burrowed_larva
 	.["evilution_level"] = evilution_level

tgui/packages/tgui/interfaces/HiveStatus.jsx

@@ -117,10 +117,16 @@ const GeneralInformation = (props, context) => {
 
   return (
     <Flex direction="column" align="center">
-      <Flex.Item textAlign="center">
-        <h3 className="whiteTitle">The Queen is in:</h3>
-        <h1 className="whiteTitle">{queen_location}</h1>
-      </Flex.Item>
+      {queen_location === null ? (
+        <Flex.Item textAlign="center">
+          <h3 className="whiteTitle">The Hive has no Queen!</h3>
+        </Flex.Item>
+      ) : (
+        <Flex.Item textAlign="center">
+          <h3 className="whiteTitle">The Queen is in:</h3>
+          <h1 className="whiteTitle">{queen_location}</h1>
+        </Flex.Item>
+      )}
       {!!hive_location && (
         <Flex.Item textAlign="center" mt={2}>
           <h3 className="whiteTitle">The Hive location is:</h3>