This is a good question IMHO, I'd love to know the answer myself.
There's the Modern Frontend Dev for Rails book. It's been rewritten to cover Hotwire but still includes a lot of stuff on traditional WPA style frontends. That's useful but I was definitely more interested in a progressive enhancement Hotwire approach based around Stimulus and Rails View Components.
I'm sure you must be aware of the Stimulus Handbook but I'll mention it anyway[2]. Also [3].
Depending on your level you could also try https://www.hotrails.dev/
1. https://pragprog.com/titles/nrclient2/modern-front-end-devel...