chore: upgrade & configure eslint to v9

Author: doinel1a

.eslintignore

@@ -0,0 +1,64 @@
+import { FlatCompat } from '@eslint/eslintrc';
+import prettierConfig from 'eslint-config-prettier/flat';
+import prettierPlugin from 'eslint-plugin-prettier/recommended';
+import sonarjs from 'eslint-plugin-sonarjs';
+import unicorn from 'eslint-plugin-unicorn';
+import tseslint from 'typescript-eslint';
+
+const compat = new FlatCompat({
+  baseDirectory: import.meta.dirname
+});
+
+export default tseslint.config(
+  {
+    ignores: ['.next']
+  },
+  ...compat.config({
+    /**
+     * Under the hood 'next' automatically configures:
+     * - eslint-plugin-next
+     * - eslint-plugin-react
+     * - eslint-plugin-react-hooks
+     * - eslint-plugin-jsx-a11y
+     */
+    extends: ['next'],
+    plugins: ['@tanstack/query']
+  }),
+  prettierConfig,
+  prettierPlugin,
+  sonarjs.configs.recommended,
+  unicorn.configs.recommended,
+  {
+    files: ['**/*.ts', '**/*.tsx'],
+    extends: [
+      ...tseslint.configs.strict,
+      ...tseslint.configs.strictTypeChecked,
+      ...tseslint.configs.stylistic,
+      ...tseslint.configs.stylisticTypeChecked
+    ],
+    rules: {
+      '@typescript-eslint/array-type': 'off',
+      '@typescript-eslint/consistent-type-definitions': 'off',
+      '@typescript-eslint/consistent-type-imports': [
+        'warn',
+        { prefer: 'type-imports', fixStyle: 'inline-type-imports' }
+      ],
+      '@typescript-eslint/no-unused-vars': ['warn', { argsIgnorePattern: '^_' }],
+      '@typescript-eslint/require-await': 'off',
+      '@typescript-eslint/no-misused-promises': [
+        'error',
+        { checksVoidReturn: { attributes: false } }
+      ]
+    }
+  },
+  {
+    linterOptions: {
+      reportUnusedDisableDirectives: true
+    },
+    languageOptions: {
+      parserOptions: {
+        projectService: true
+      }
+    }
+  }
+);

.eslintrc.cjs

@@ -56,36 +56,35 @@
   "devDependencies": {
     "@commitlint/cli": "19.8.0",
     "@commitlint/config-conventional": "19.8.0",
+    "@eslint/eslintrc": "3.3.1",
     "@ianvs/prettier-plugin-sort-imports": "4.4.1",
+    "@next/eslint-plugin-next": "15.3.2",
     "@playwright/test": "1.52.0",
     "@tanstack/eslint-plugin-query": "5.74.7",
     "@total-typescript/ts-reset": "0.6.1",
-    "@types/eslint": "9.6.1",
     "@types/node": "22.15.15",
     "@types/qrcode": "1.5.5",
     "@types/react": "19.1.3",
     "@types/react-dom": "19.1.3",
-    "@typescript-eslint/eslint-plugin": "8.32.0",
-    "@typescript-eslint/parser": "8.32.0",
     "autoprefixer": "10.4.21",
     "cssnano": "7.0.7",
-    "eslint": "8.57.0",
+    "eslint": "9.26.0",
     "eslint-config-next": "15.3.2",
     "eslint-config-prettier": "10.1.3",
     "eslint-plugin-jsx-a11y": "6.10.2",
     "eslint-plugin-prettier": "5.4.0",
-    "eslint-plugin-promise": "7.2.1",
     "eslint-plugin-react": "7.37.5",
     "eslint-plugin-react-hooks": "5.2.0",
-    "eslint-plugin-sonarjs": "0.25.1",
-    "eslint-plugin-unicorn": "56.0.1",
+    "eslint-plugin-sonarjs": "3.0.2",
+    "eslint-plugin-unicorn": "59.0.1",
     "husky": "9.1.7",
     "lint-staged": "15.5.2",
     "postcss": "8.5.3",
     "prettier": "3.5.3",
     "prettier-plugin-tailwindcss": "0.6.11",
     "sass": "1.87.0",
     "tailwindcss": "3.4.17",
-    "typescript": "5.8.3"
+    "typescript": "5.8.3",
+    "typescript-eslint": "8.32.0"
   }
 }