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/lodash/_objectToString.js

@@ -0,0 +1,22 @@
+/** Used for built-in method references. */
+var objectProto = Object.prototype;
+
+/**
+ * Used to resolve the
+ * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
+ * of values.
+ */
+var nativeObjectToString = objectProto.toString;
+
+/**
+ * Converts `value` to a string using `Object.prototype.toString`.
+ *
+ * @private
+ * @param {*} value The value to convert.
+ * @returns {string} Returns the converted string.
+ */
+function objectToString(value) {
+  return nativeObjectToString.call(value);
+}
+
+module.exports = objectToString;