raj00700777-ctrl/discord-relay-bot ? reverse-engineered prompt

Build me a simple Discord relay bot in JavaScript.

I want it to connect to Discord with a bot token, then forward messages from one channel to another so people in both places can see what’s being said. It should be easy to configure which channel or channels it listens to and where it sends messages. If someone posts a message, the bot should relay the content cleanly and avoid obvious loops or duplicated messages.

Please keep it lightweight and straightforward, with a single entry file if possible, and make sure it runs from the command line with clear setup instructions in the project. If you need to check current Discord bot docs online, go ahead. Also include basic error handling so it does not crash if the bot loses connection or gets a bad message.