feat: update to utilise the new ESLint flat file config.

[maclong9]

Is your feature request related to a problem? Please describe.

This cli tool is great for setting up a project with a good base stack really quickly, only snag in productivity at the moment is requiring the conversion of .eslintrc.json to the new eslint.config.{m|c}js format.

Describe the solution you'd like to see

Update the standard configuration to utilise the new flat file configuration.

Describe alternate solutions

Write a codemod script that can be run by developers who want to use the new format.

Additional information

No response

[juliusmarminge]

only snag in productivity at the moment is requiring the conversion of .eslintrc.json to the new eslint.config.{m|c}js format.

This is a bit of a stretch given a lot (probably a large majority actually) still doesn't support FlatConfig natively

[juliusmarminge]

Reviving this now that v8 has reached EOL.

Next 15 has official support for v9 (https://nextjs.org/blog/next-15-rc2#eslint-9-support) and also flat config (https://x.com/feedthejim/status/1846502242590802180)

If we assume Next 15 will be marked stable next week at NextConf we could start preparing a PR with the necessary bumps

[TheCukitoDev]

Now Next.js 15 is stable...