Handle null values in ThermalGenerator progress bars

[Ossa88]

About The Pull Request

This pull request improves the robustness of the ThermalGenerator interface by ensuring that TGUI NtOS TypeScript page has a fall back should a undefined variable exist. This generally happens when a TEG is created by players.

Why It's Good For The Game

Player craft able TEG's have an error were some values inside the ThermalGenerator.js which results in a NtOS blue screen.

Changelog

🆑
fix: Should stop possible null values for player constructed TEG systems
/:cl:

[Ossa88]

FYI This has yet to be tested. I just needed to save the work and branch, as I have developed a bad habit of losing working bug fix branches.

[github-actions]

This PR has been inactive for a month. This means it is at risk of being auto closed in a week, please address any outstanding review items and ensure your PR is finished, if these are all true and you are auto-staled anyway, you need to actively ask maintainers if your PR will be merged. Once you have done any of the previous actions then you should request a maintainer remove the stale label on your PR, to reset the stale timer. If you feel no maintainer will respond in that time, you may wish to close this PR youself, while you seek maintainer comment, as you will then be able to reopen the PR yourself