Very nice article. This was the intro I needed having not yet looked closely at LNURL.

However, when you say "your wallet will translate that into URL", do you mean there's an actual process of discovery not here described, or that the LNURL is a convention meaning that all websites serving LNURLs must follow this pattern so wallets can safely assume the final URL based on the username format?

In LNURL-pay in general, the URL (encoded with bech32 encoding in QR code) can be anything, for example

In Lightning Address (subset of LNURL-pay), final URL is ALWAYS ".../.well-known/lnurlp/<username>".