Add JsInterpreter to replace Rhino usage

[Luna712]

I added 326 test cases for this, all of which pass locally. When adding tests I specifically targeted some common uses of rhino by extensions, and additionally added things extensions may want or need to use in the future. We can also expand those tests should something else come up in the future.

[Luna712]

This should now be ready for review. I ran all the tests and they worked, fixed a couple things, and added a simpler API.

[fire-light42]

It looks like the JS interpreter does not handle the JSFuck obfuscation technique, which abuses easily overlooked parts of standard JS to obfuscate code, it should be very easy to generate test cases.

Would it be possible to support this or would it be too much scope creep? Even if it cannot be fully supported it might reveal some easy-to-fix edge cases.

[Luna712]

It should be possible to support it although I am not entirely sure how at the moment. I aimed for this to support a lot of the standard JS spec, and didn't really go beyond it. I tried to support everything I found extensions using Rhino for and added test cases for some of those uses. I think if we do support it, we can, but perhaps should be a separate PR as that is kinda a different scope then what this was aiming for but up to you, I could look more into this this weekend though if you want.

[fire-light42]

I will also do some testing on the real-world usage of the JS helpers to determine if this is required. Currently it does not seem like a blocker.

[Luna712]

Supporting this does expose other edge case bugs here. I have a patch I will push soon that will support this, fix numerous other things, and add more than 150 new test cases for the edge case bugs and JSFuck format.

[Luna712]

I do want to note also, I did not want to reinvente JavaScript here so this definitely does not support everything, if something needs some other support added we can add it later. I decided to add support for instanceof in my recent commit here only because I found that one could have some use for some scripts potentially and we support typeof. But it still doesn't support some things like some less used Math functions, static functions like Array.isArray, Array.of, etc.... I could easily add it later if it's something we need or want though. Things like console.* are just silently swallowed no-ops so they don't cause noise but also don't fail the scripts. This can all be changed later if necessary. This is designed to be lighter weight, so I didn't want to do everything.