Re-themes the Delta to N+S Logistics (shiptest-ss13#2967)

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## About The Pull Request

![delta-ns](https://github.com/shiptest-ss13/Shiptest/assets/60533805/5d25128b-4603-46ea-b498-22551d9d9555)

![n-s_decals](https://github.com/shiptest-ss13/Shiptest/assets/60533805/62d6149f-9d34-4a09-abf3-f2b35f5b0a6f)

Updates the delta (decal swaps and outfit changes) to be properly
associated with N+S Logistics rather than just Nanotrasen, and adds N+S
floor decals and signs.

## Why It's Good For The Game

New lore representation is good.

## Changelog

:cl:
tweak: Made the Delta more obviously affiliated with N+S Logistics
/:cl:

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_maps/configs/nanotrasen_delta.json

@@ -1,7 +1,7 @@
 {
 	"$schema": "https://raw.githubusercontent.com/shiptest-ss13/Shiptest/master/_maps/ship_config_schema.json",
 	"map_name": "Delta-class Frigate",
-	"prefix": "NTSV",
+	"prefix": "NSSV",
 	"namelists": [
 		"GENERAL",
 		"SPACE",
@@ -10,7 +10,7 @@
 		"NANOTRASEN"
 	],
 	"map_short_name": "Delta-class",
-	"description": "The Delta is a compact and advanced mining ship that supplements its comparatively small organic crew with a full suite of robotics facilities, including an AI and a host of mining and logistics drones and cyborgs. While much-loved by Nanotrasen logisticians for their minimal upkeep and high cost efficiency, Deltas are far less popular among the crews chosen to operate them, as they are severely lacking in crew accommodations and defensive armament.",
+	"description": "The Delta is a compact and advanced mining ship that supplements its comparatively small organic crew with a full suite of robotics facilities, including an AI and a host of mining and logistics drones and cyborgs. The Delta's low logistical footprint has thoroughly endeared it to N+S Logistics' upper management, but its cramped accomodations and lackluster defensive armament make it distinctly unpopular with the company's spacefaring employees.",
 	"tags": [
 		"Science",
 		"Robotics"
@@ -19,20 +19,20 @@
 	"starting_funds": 4000,
 	"job_slots": {
 		"Captain": {
-			"outfit": "/datum/outfit/job/nanotrasen/captain",
+			"outfit": "/datum/outfit/job/nanotrasen/captain/ns",
 			"officer": true,
 			"slots": 1
 		},
-		"Roboticist": {
+		"Robotics Contractor": {
 			"outfit": "/datum/outfit/job/nanotrasen/roboticist",
 			"slots": 2
 		},
 		"Engineer": {
 			"outfit": "/datum/outfit/job/nanotrasen/engineer",
 			"slots": 1
 		},
-		"Assistant": {
-			"outfit": "/datum/outfit/job/nanotrasen/assistant",
+		"Deckhand": {
+			"outfit": "/datum/outfit/job/nanotrasen/cargo_tech",
 			"slots": 3
 		}
 	},