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-pure/full/array/is-template-object.js

@@ -0,0 +1,5 @@
+'use strict';
+require('../../modules/esnext.array.is-template-object');
+var path = require('../../internals/path');
+
+module.exports = path.Array.isTemplateObject;