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/internals/get-iterator.js

@@ -0,0 +1,14 @@
+'use strict';
+var call = require('../internals/function-call');
+var aCallable = require('../internals/a-callable');
+var anObject = require('../internals/an-object');
+var tryToString = require('../internals/try-to-string');
+var getIteratorMethod = require('../internals/get-iterator-method');
+
+var $TypeError = TypeError;
+
+module.exports = function (argument, usingIterator) {
+  var iteratorMethod = arguments.length < 2 ? getIteratorMethod(argument) : usingIterator;
+  if (aCallable(iteratorMethod)) return anObject(call(iteratorMethod, argument));
+  throw new $TypeError(tryToString(argument) + ' is not iterable');
+};