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/@babel/traverse/lib/hub.js

@@ -0,0 +1,19 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.default = void 0;
+class Hub {
+  getCode() {}
+  getScope() {}
+  addHelper() {
+    throw new Error("Helpers are not supported by the default hub.");
+  }
+  buildError(node, msg, Error = TypeError) {
+    return new Error(msg);
+  }
+}
+exports.default = Hub;
+
+//# sourceMappingURL=hub.js.map