Initial commit: Developer Tools MVP with visual editor

- Complete React app with 7 developer tools
- JSON Tool with visual structured editor
- Serialize Tool with visual structured editor
- URL, Base64, CSV/JSON, Beautifier, Diff tools
- Responsive navigation with dropdown menu
- Dark/light mode toggle
- Mobile-responsive design with sticky header
- All tools working with copy/paste functionality

node_modules/jest-resolve/build/isBuiltinModule.js

@@ -0,0 +1,36 @@
+'use strict';
+
+Object.defineProperty(exports, '__esModule', {
+  value: true
+});
+exports.default = isBuiltinModule;
+
+function _module() {
+  const data = _interopRequireDefault(require('module'));
+
+  _module = function () {
+    return data;
+  };
+
+  return data;
+}
+
+function _interopRequireDefault(obj) {
+  return obj && obj.__esModule ? obj : {default: obj};
+}
+
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+// TODO: remove when we drop support for node v10 - it is included from node v12
+const EXPERIMENTAL_MODULES = ['worker_threads'];
+const BUILTIN_MODULES = new Set(
+  _module().default.builtinModules.concat(EXPERIMENTAL_MODULES)
+);
+
+function isBuiltinModule(module) {
+  return BUILTIN_MODULES.has(module);
+}