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/style-loader/dist/runtime/setAttributesWithoutAttributes.js

@@ -0,0 +1,10 @@
+"use strict";
+
+/* istanbul ignore next  */
+function setAttributesWithoutAttributes(styleElement) {
+  var nonce = typeof __webpack_nonce__ !== "undefined" ? __webpack_nonce__ : null;
+  if (nonce) {
+    styleElement.setAttribute("nonce", nonce);
+  }
+}
+module.exports = setAttributesWithoutAttributes;