Migrate ESLint to v9.0.0

[eboileau]

Aims/objectives.

Major release of ESLint with several breaking changes.

A clear and concise description of todo items.

Tested with eslint/config but would prefer using @vue/eslint-config-typescript.

import js from "@eslint/js";
import globals from "globals";
import tseslint from "typescript-eslint";
import pluginVue from "eslint-plugin-vue";
import { defineConfig } from "eslint/config";


export default defineConfig([
  { files: ["**/*.{js,mjs,cjs,ts,mts,cts,vue}"], plugins: { js }, extends: ["js/recommended"] },
  { files: ["**/*.{js,mjs,cjs,ts,mts,cts,vue}"], languageOptions: { globals: globals.browser } },
  tseslint.configs.recommended,
  pluginVue.configs["flat/essential"],
  { files: ["**/*.vue"], languageOptions: { parserOptions: { parser: tseslint.parser } } },
]);

Package dependencies need to be cleaned up.

Upgrading at the same time

@vue/eslint-config-typescript  ^13.0.0  →  ^14.5.0
eslint                         ^8.57.1  →  ^9.28.0
eslint-plugin-vue              ^9.33.0  →  ^10.1.0
postcss                         ^8.5.3  →   ^8.5.4
prettier                        ^2.8.8  →   ^3.5.3
typescript                      ~5.4.0  →   ~5.8.3
vitest                          ^3.1.4  →   ^3.2.1
vue                            ^3.2.47  →  ^3.5.16

Type checking fails with error TS4082: Default export of the module has or is using private name 'Props'.