[ukuina]

Well done!

What are these types of web apps that have no backend called?

You still need the CDN, so they're not classically serverless (https://www.sqlite.org/serverless.html)

[jarofgreen]

Static?

[franky47]

Jamstack https://jamstack.org/

[austinjp]

Website, not web app. Static website if it has no backend. Strictly speaking, 'static' used to mean no JavaScript either, so perhaps 'jamstack' is the appropriate neologism.