Adds icon for hive core and cluster to Xeno tacmap (#4820)

There was supposed to be an icon for the hive core but it doesn't seem
to exist.

I added one for hive core and cluster


![dreammaker_2023-11-01_21-26-47](https://github.com/cmss13-devs/cmss13/assets/25027759/38f4d39f-4e1d-4874-bc8d-1a9a020a4604)


![2023-11-01_21-18-05](https://github.com/cmss13-devs/cmss13/assets/25027759/e0cf5302-004b-4a2a-9370-a8fcfac961a6)

My sprites even at this level are awful. If someone who is actually
artistic could make better ones I will use those. Likewise if you would
like to make 2 states for the core, damaged and healthy I can restore
the intended functionality of displaying a different icon for a damaged
core.

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# Changelog
:cl:
add: Xeno tacmap icons for hive core and clusters.
/:cl:

---------

Co-authored-by: Lee B <[email protected]>

code/modules/cm_aliens/structures/special/hive_cluster.dm

@@ -23,9 +23,15 @@
 /obj/effect/alien/resin/special/cluster/Initialize(mapload, hive_ref)
 	. = ..()
 	node = place_node()
+	update_minimap_icon()
+
+/obj/effect/alien/resin/special/cluster/proc/update_minimap_icon()
+	SSminimaps.remove_marker(src)
+	SSminimaps.add_marker(src, z, MINIMAP_FLAG_XENO, "cluster")
 
 /obj/effect/alien/resin/special/cluster/Destroy()
 	QDEL_NULL(node)
+	SSminimaps.remove_marker(src)
 	return ..()
 
 /obj/effect/alien/resin/special/cluster/attack_alien(mob/living/carbon/xenomorph/M)

code/modules/cm_aliens/structures/special/pylon_core.dm

@@ -248,7 +248,7 @@
 
 /obj/effect/alien/resin/special/pylon/core/proc/update_minimap_icon()
 	SSminimaps.remove_marker(src)
-	SSminimaps.add_marker(src, z, MINIMAP_FLAG_XENO, "core[health < (initial(health) * 0.5) ? "_warn" : "_passive"]")
+	SSminimaps.add_marker(src, z, MINIMAP_FLAG_XENO, "core")
 
 /obj/effect/alien/resin/special/pylon/core/process()
 	. = ..()