Use ESLint extends

[joshkel]

Since March of this year, ESLint supports and recommends using extends for flat configurations (instead of having to manually spread the pieces of the configuration.

[G-Rath]

It looks like that is a feature of the defineConfig helper, not actually ESLint itself - personally I think I'd prefer to stick with what we have for now since the helpers are still evolving and it keeps this example consistent with others

[joshkel]

Thanks for the correction, @G-Rath. I failed to realize that extends requires defineConfig.

defineConfig is recommended throughout the ESLint documentation; from what I've been able to follow of ESLint 9.x's development, it's quite stable. I've updated the remaining examples, but, of course, it's up to you all whether you want to update this plugin's docs to match.