Nonstandard characters from folder path breaks the file searcher

The super common error we keep seeing from mainmenu.lua is an error where Olympus fails to retrieve the given file from a string path containing nonUTF-8 characters. I'm not 100% sure how to fix this but this should be an easy thing to resolve, i think.

Error comes from [this point](https://github.com/EverestAPI/Olympus/blob/main/src/scenes/mainmenu.lua#L244-L245), and has been mentioned fairly frequently in modding help over about a year

Error appears as:
Error

threader.lua:544: thread#3