[code-infra] Migration to ESLint v9

[oliviertassinari]

Summary

https://eslint.org/blog/2024/04/eslint-v9.0.0-released/.

At the same time, we need to migrate our file format to the new one https://eslint.org/docs/latest/use/configure/configuration-files-deprecated. In practice, it means for instance that files like

material-ui/packages/mui-icons-material/.eslintrc.js

Lines 1 to 7 in f9a5847

	module.exports = {
	rules: {
	// needed for mustache and temp
	'import/no-unresolved': 'off',
	'import/extensions': 'off',
	},
	};

are not allowed. Everything should be in the root eslint.config.js file. I think this is great, it's much simpler to manage the configuration like this, as well as share it with other repositories.

---

Off-topic, related improvements to the code-infra around ESLint (could go to separate issues if approved by the team):

1. From [code-infra] Rely on @mui/monorepo/.eslintrc base-ui#352 (comment) It would be great to split the config file to export chunks that are Material UI specific (<10% likely) and other chunks (>90% likely) that are code-infra related. https://github.com/mui/material-ui/blob/f9a5847671bb74e710194efb1a05fb0d7d65a6a2/.eslintrc.js
2. We need to propagate config up and down, some stuff are in, e.g. MUI X but should be shared everywhere, and others shouldn't be in MUI X in the first place
3. We could avoid a class of bug by propagating https://github.com/mui/mui-x/blob/4b07dfdbf67f5a6798ee71992656f40250124a50/.eslintrc.js#L162 everywhere.

Examples

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Motivation

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