[eprh]: Fix config examples and update instructions in README.md

[mdj-uk]

Summary

Fixes #34779

Also adds instructions for using latest compiler powered rules.

How did you test this change?

• I've tested that you can copy and paste into newly created vite apps (with and without typescript) with eslint v9 and eprh v6.1.1 (i.e. will fix https://github.com/mdj-uk/vite-react-no-ts (sandbox) and https://github.com/mdj-uk/vite-react-ts (sandbox)
• I've not considered legacy (non-flat) eslint config, or older versions of eprh

[josephsavona]

Thanks for the contribution! We're already working on an update to the readme in #34757 - heads to @poteto in case we want to pull in any content from this PR.

[mdj-uk]

Closing this as it's now out of date with the release of eprh v7.

Though there's still (imho) an issue with the sample eslint config not working out of the box. See my comment at #34779 (comment). Happy to submit a PR based on that if it's helpful.

PS: nice job everyone on your talks this week - really enjoyed them! And congrats on release of compiler v1.0