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/es-abstract/2025/SetDataHas.js

@@ -0,0 +1,26 @@
+'use strict';
+
+var $TypeError = require('es-errors/type');
+
+var CanonicalizeKeyedCollectionKey = require('./CanonicalizeKeyedCollectionKey');
+var IsArray = require('./IsArray');
+var SameValue = require('./SameValue');
+
+var some = require('../helpers/some');
+
+// https://262.ecma-international.org/16.0/#sec-setdatahas
+
+module.exports = function SetDataHas(setData, value) {
+	if (!IsArray(setData) && setData !== 'EMPTY') {
+		throw new $TypeError('Assertion failed: `setData` must be a List or ~EMPTY~');
+	}
+
+	// if (SetDataIndex(setData, value) === 'NOT-FOUND') { return false; } // step 1
+	// return true; // step 2
+
+	var canonValue = CanonicalizeKeyedCollectionKey(value);
+
+	return some(setData, function (e) {
+		return SameValue(e, canonValue);
+	});
+};