fix(deps): upgrade eslint and plugins to 9.39.4 (#201701)

* fix(deps): upgrade eslint and plugins to 10.2.0

* chore: manual lint-fix

* chore: automatic lint-fix

* feat(repo): github actions - lint - use node v24

because it is linting (not runtime), so why not
to use the latest stable Node version

* fix: remove @stylistic/eslint-plugin (in favor of prettier)

* fix: eslint uses `ecmaVersion` 2025

* fix: eslint's "mocha" config is isolated (for test files only)

for example `describe` is not considered "global" outside the
test files. the same for all other "eslint/mocha" rules -
they are applied only to files in `/tests` folder.

* chore: update package-lock.json after eslint upgrade

eslint.config.mjs

@@ -0,0 +1,67 @@
+import globals from 'globals';
+import pluginEslintJs from '@eslint/js';
+import pluginMocha from 'eslint-plugin-mocha';
+import configEslintConfigPrettier from 'eslint-plugin-prettier/recommended';
+
+export default [
+    pluginEslintJs.configs.recommended,
+    {
+        name: 'whatsapp-web.js/default/rules',
+        plugins: {
+            mocha: pluginMocha,
+        },
+        languageOptions: {
+            ecmaVersion: 2025,
+
+            globals: {
+                ...globals.browser,
+                ...globals.commonjs,
+                ...globals.es6,
+                ...globals.node,
+
+                Atomics: 'readonly',
+                SharedArrayBuffer: 'readonly',
+            },
+        },
+        rules: {
+            'no-unused-vars': [
+                'error',
+                {
+                    // TODO: args can be uncommented, but there is code, that causes lint-errors
+                    // args: 'all',
+                    vars: 'all',
+                    caughtErrorsIgnorePattern: '^ignoredError',
+                },
+            ],
+        },
+    },
+    {
+        // be careful, "recommended" settings object has 4 fields:
+        // - name (string)
+        // - plugins (object)
+        // - languageOptions (object)
+        // - rules (object)
+        //
+        // by simple "adding" any of mentioned fields to this object
+        // you REPLACE the "recommended" value.
+        // If you want to PATCH it - consider nested "..." spread operator
+        ...pluginMocha.configs.recommended,
+        name: 'whatsapp-web.js/default/mocha',
+
+        files: ['tests/**/*'],
+    },
+    {
+        name: 'whatsapp-web.js/default/ignores',
+        ignores: [
+            'node_modules',
+            'dist',
+            'coverage',
+            'docs',
+            '*.min.js',
+            '.wa-version',
+            '.wwebjs_auth',
+            '.wwebjs_cache',
+        ],
+    },
+    configEslintConfigPrettier,
+];