feat!: switch to eslint 9 flat config

[egilsster]

Integration steps:

1. Install package with latest configs (from this PR)
2. Install eslint 9 and change your lint script to use it (e.g. eslint .)
3. rename your config to eslint.config.js (if you have "type": "module" in your package json) / eslint.config.mjs (if otherwise)
   example config that uses typescript, react, vitest, react-query plugin:

// @ts-check
import qlik from "@qlik/eslint-config";
import pluginQuery from "@tanstack/eslint-plugin-query";

export default qlik.compose(
  ...qlik.configs.react,
  ...qlik.configs.vitest,
  ...pluginQuery.configs["flat/recommended"],
  {
    rules: {
      // Override rules if needed
    },
  },
  // In its own object so it's global
  {
    ignores: ["dist", "node_modules", "script"],
  },
);

4. If you arent using typescript to build your project and use it solely as a 'linter', then make it include all files "include": [".*", "**/*"] in your tsconfig

run your lint script

[changeset-bot]

🦋 Changeset detected

Latest commit: 00e32d3

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@qlik/eslint-config	Major

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