The Mechening: Shiptest Edition (#3035)

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## About The Pull Request
Hello there! Hope you didn't miss me this soon ;)

This PR ports a very recent PR on /tg/, done by the extremely talented
INFRARED_BARON and PR'd by @githubuser4141 (known as wastelandmain on
discord)
- tgstation/tgstation#83024

Since we do have a few original mechs on Shiptest as well, the CLIP
mechs have also been resprited entirely to match the new suits we will
now see in game!


![image](https://github.com/shiptest-ss13/Shiptest/assets/77556824/3b03bbc3-a1ba-4403-9e3b-aa9c84c21b35)

![image](https://github.com/shiptest-ss13/Shiptest/assets/77556824/1df55795-5f6b-4dfe-a5b7-170eea7b24d4)

### This PR has been ported with the consent of the original PR author,
as well as the original spriter.
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## Why It's Good For The Game
They're a lot prettier than what we currently have, and while we wait
for the fabled mech rework, this is a good enough visual stopgap to not
make me want to tear my eyeballs out.
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## Changelog

:cl: INFRARED_BARON, PositiveEntropy
imageadd: Resprites nearly every mech!
/:cl:

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