chore: migrate ESLint config

eslint.config.js

@@ -0,0 +1,46 @@
+import js from '@eslint/js';
+import prettierConfig from 'eslint-plugin-prettier/recommended';
+import jestPlugin from 'eslint-plugin-jest';
+import globals from 'globals';
+
+export default [
+  {
+    files: ['**/*.js'],
+  },
+  {
+    // Ignore patterns
+    ignores: ['coverage/**'],
+  },
+  js.configs.recommended,
+  prettierConfig,
+  {
+    // Base settings
+    languageOptions: {
+      ecmaVersion: 'latest',
+      sourceType: 'module',
+      globals: {
+        ...globals.node,
+        ...globals.es6,
+      },
+    },
+    rules: {
+      'prettier/prettier': 'warn',
+    },
+  },
+  {
+    // Jest settings for test files
+    files: ['**/*.test.js'],
+    languageOptions: {
+      globals: {
+        ...globals.jest,
+      },
+    },
+    plugins: {
+      jest: jestPlugin,
+    },
+    rules: {
+      ...jestPlugin.configs.recommended.rules,
+      ...jestPlugin.configs.style.rules,
+    },
+  },
+];

package.json

@@ -9,7 +9,7 @@
   "license": "MIT",
   "type": "module",
   "scripts": {
-    "lint:eslint": "eslint . --ext .js",
+    "lint:eslint": "eslint .",
     "lint:prettier": "prettier ./**/*.{json,md,yml} --check",
     "lint": "npm run lint:eslint && npm run lint:prettier",
     "lint:fix": "npm run lint:eslint -- --fix && npm run lint:prettier -- --write",