Adds an alternative to the navigate verb (#5737)

## About The Pull Request

Adds **Plexagon NavSec**, a new PDA app available on the NT store with
no access restriction, pre-loaded on the assistant PDA.

NavSec scans `SSmachines.processing_apcs` at runtime to build a
complete, alphabetical list of every station area with an APC. Selecting
one points the standard NtosRadar arrow (Same one as the nukie
pinpointer/ Lifeline app) toward it. Results are filtered to
`/area/station` subtypes, so antagonist ships, Centcomm, player created
naughty rooms, and away missions are excluded; Yes, I thought about the
use case of "use it to find antag hidey holes" and made sure to nip that
pre-emptively.

**This is not a replacement for the Navigate verb.** They answer
different questions:

- **Navigate** asks *"how do I get there?"* It provides pathing, but
requires mapper-placed waypoints, gates routing on your current ID
access, and shits the bed when either of those is missing. Also it has a
really annoying and unnecessary cooldown.
- **NavSec** asks *"which way?"* It finds the APC for the area and
points at it. No pathing, no access check, no waypoint dependency, no
mapping maintenance burden. It trusts you to figure out your own
flapping.

The tradeoff is intentional. The implementation is light: no new
subsystems, no new TGUI, no mapping work. It piggybacks entirely on APC
registration, which already happens for free at round start.

## Why It's Good For The Game

There is a category of frustration in this game that has nothing to do
with skill, experience, or the actual difficulty of the task at hand.
You are an antagonist with an objective, a secoff tasked to patrol for a
bounty, or a new player following a job order, and you are stuck
patrolling a random corridor in hopes that your destination will
magically present itself because the room you need is called something
like *"Starboard Aft Secondary Maintenance"* or *"The Clown's Anus"* and
you have been wandering around for four minutes. Hell maybe you're a
really dim traitor and need help finding the armory to blow it up.

The Navigate verb is the official answer to this and is frequently
insufficient:

- It does not cover many obscure areas
- It requires mappers to actively maintain waypoints
- It will just straight up not be able to get you to your destination
half the time

New players probably aren't equipped with the knowledge to troubleshoot
Navigate's temperamentality

NavSec sidesteps all of that. Every station area that has power has an
APC. The list is always complete and always current. The app ships
pre-loaded on the assistant PDA so new players encounter it without
having to know it exists, and is free to download for everyone else if
you're not an assistant and need it anyway.

Sure, we should still think about improving the navigate verb, but this
is a good alternative in the meantime.

## Proof Of Testing

Spawned as assistant, opened PDA, confirmed NavSec present. Hit Scan,
confirmed alphabetical area list populated. Walked directly to aft port
maintinence despite not knowing what aft or port means, GREAT SUCCESS!
<img width="2551" height="1316" alt="image"
src="https://github.com/user-attachments/assets/ec415202-7b06-458e-81a0-7223efc06e3c"
/>

## Changelog

🆑
add: Added Plexagon NavSec, a PDA app that locates any station area by
tracking its APC. No access required. Available on the NT store and
pre-loaded on the assistant PDA.
qol: New players and anyone dropped into an unfamiliar station layout
can now find obscurely named rooms without relying on the Navigate verb
or prior map knowledge.
/🆑

modular_zubbers/modules/plexagon_navsec/code/navsec.dm

@@ -0,0 +1,34 @@
+/// APC-based area navigator. Displays all station areas with APCs and points an arrow toward the selected one.
+/datum/computer_file/program/radar/navsec
+	filename = "plexagonnavsec"
+	filedesc = "Plexagon NavSec"
+	extended_desc = "Never get lost again. Plexagon NavSec indexes every area on the station and points you straight to it, no matter how obscure the name or unfamiliar the layout. Perfect for new crew and anyone transferred to a station they've never set foot on."
+	program_flags = PROGRAM_ON_NTNET_STORE | PROGRAM_REQUIRES_NTNET
+	program_icon = "location-arrow"
+	size = 2
+
+/datum/computer_file/program/radar/navsec/find_atom()
+	return ..() || (locate(selected) in SSmachines.processing_apcs)
+
+/datum/computer_file/program/radar/navsec/scan()
+	objects = list()
+	var/list/name_to_apc = list()
+	for(var/obj/machinery/power/apc/station_apc as anything in SSmachines.processing_apcs)
+		var/area/apc_area = station_apc.area
+		if(!istype(apc_area, /area/station))
+			continue
+		if(!trackable(station_apc))
+			continue
+		name_to_apc[apc_area.name] = station_apc
+	sortTim(name_to_apc, /proc/cmp_text_asc)
+	for(var/area_name in name_to_apc)
+		var/obj/machinery/power/apc/station_apc = name_to_apc[area_name]
+		var/list/apc_info = list(
+			ref = REF(station_apc),
+			name = area_name,
+		)
+		objects += list(apc_info)
+
+/obj/item/modular_computer/pda/assistant/install_default_programs()
+	. = ..()
+	store_file(new /datum/computer_file/program/radar/navsec)

tgstation.dme

@@ -10227,6 +10227,7 @@
 #include "modular_zubbers\modules\awaymissions_zubbers\Maintsroom\spawner_maintsroom.dm"
 #include "modular_zubbers\modules\jobs\job_types\chaplain\chaplain_nullrod.dm"
 #include "modular_zubbers\modules\lewd_clothing\latex_halfcatsuit.dm"
+#include "modular_zubbers\modules\plexagon_navsec\code\navsec.dm"
 #include "modular_zubbers\modules\plexagon_selfserve\code\off_duty_component.dm"
 #include "modular_zubbers\modules\plexagon_selfserve\code\plexagon_selfserve.dm"
 #include "modular_zubbers\modules\plexagon_selfserve\code\shame_box.dm"