feat: create a JS helpers class

[a2937]

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Closes #XXXXX

In my opinion, it does come up fairly often that we use regex to ensure that variables are actually present in functions with default values; and I think the potential spacing issues aren't generally worth with it when we can just manually extract them.

I also tried to do some house-keeping and hopefully keep eslint from reformatting the fixtures as it is very space sensitive. As I use Visual Studio to edit Typescript, I also added some of the contents of VisualStudio.gitignore to the local gitignore. I will be be happy to remove the unrelated content and discuss them at a later date.

[a2937]

Did I get it, as all tests seem to pass?