server/browser has minimum functionality

This works. That's about all the good I can say about it.

If I were to do this project correctly, I would split my server into a
server class. Methods would be defined for GET and POST (rather than if,
elsif)

I would have a class to handle the file. I would handle the json data
there.

I would do a lot differently. But this works, and I learned about
sockets.