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/_baseGetAllKeys.js

@@ -0,0 +1,20 @@
+var arrayPush = require('./_arrayPush'),
+    isArray = require('./isArray');
+
+/**
+ * The base implementation of `getAllKeys` and `getAllKeysIn` which uses
+ * `keysFunc` and `symbolsFunc` to get the enumerable property names and
+ * symbols of `object`.
+ *
+ * @private
+ * @param {Object} object The object to query.
+ * @param {Function} keysFunc The function to get the keys of `object`.
+ * @param {Function} symbolsFunc The function to get the symbols of `object`.
+ * @returns {Array} Returns the array of property names and symbols.
+ */
+function baseGetAllKeys(object, keysFunc, symbolsFunc) {
+  var result = keysFunc(object);
+  return isArray(object) ? result : arrayPush(result, symbolsFunc(object));
+}
+
+module.exports = baseGetAllKeys;