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/_baseIndexOf.js

@@ -0,0 +1,20 @@
+var baseFindIndex = require('./_baseFindIndex'),
+    baseIsNaN = require('./_baseIsNaN'),
+    strictIndexOf = require('./_strictIndexOf');
+
+/**
+ * The base implementation of `_.indexOf` without `fromIndex` bounds checks.
+ *
+ * @private
+ * @param {Array} array The array to inspect.
+ * @param {*} value The value to search for.
+ * @param {number} fromIndex The index to search from.
+ * @returns {number} Returns the index of the matched value, else `-1`.
+ */
+function baseIndexOf(array, value, fromIndex) {
+  return value === value
+    ? strictIndexOf(array, value, fromIndex)
+    : baseFindIndex(array, baseIsNaN, fromIndex);
+}
+
+module.exports = baseIndexOf;