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/core-js/es/reflect/index.js

@@ -0,0 +1,19 @@
+'use strict';
+require('../../modules/es.object.to-string');
+require('../../modules/es.reflect.apply');
+require('../../modules/es.reflect.construct');
+require('../../modules/es.reflect.define-property');
+require('../../modules/es.reflect.delete-property');
+require('../../modules/es.reflect.get');
+require('../../modules/es.reflect.get-own-property-descriptor');
+require('../../modules/es.reflect.get-prototype-of');
+require('../../modules/es.reflect.has');
+require('../../modules/es.reflect.is-extensible');
+require('../../modules/es.reflect.own-keys');
+require('../../modules/es.reflect.prevent-extensions');
+require('../../modules/es.reflect.set');
+require('../../modules/es.reflect.set-prototype-of');
+require('../../modules/es.reflect.to-string-tag');
+var path = require('../../internals/path');
+
+module.exports = path.Reflect;