Thanks for including the source code and a screenshot of the exact error. This puts you above most of the new members.
With that being said, could you only include (in thread) the relevant portion of the scripts? I personally don't like downloading code. Simply copy the code and use
If you want my guess, I would say it's a corrupt file or non-standard character set (Eg. utf-8).
PS, Node.js is considered server-side, no?