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/GeneratorResumeAbrupt.js

@@ -0,0 +1,51 @@
+'use strict';
+
+var $TypeError = require('es-errors/type');
+
+var CompletionRecord = require('./CompletionRecord');
+var CreateIteratorResultObject = require('./CreateIteratorResultObject');
+var GeneratorValidate = require('./GeneratorValidate');
+var NormalCompletion = require('./NormalCompletion');
+
+var SLOT = require('internal-slot');
+
+// https://262.ecma-international.org/16.0/#sec-generatorresumeabrupt
+
+module.exports = function GeneratorResumeAbrupt(generator, abruptCompletion, generatorBrand) {
+	if (
+		!(abruptCompletion instanceof CompletionRecord)
+		|| (abruptCompletion.type() !== 'return' && abruptCompletion.type() !== 'throw')
+	) {
+		throw new $TypeError('Assertion failed: abruptCompletion must be a `return` or `throw` Completion Record');
+	}
+
+	var state = GeneratorValidate(generator, generatorBrand); // step 1
+
+	if (state === 'SUSPENDED-START') { // step 2
+		SLOT.set(generator, '[[GeneratorState]]', 'COMPLETED'); // step 3.a
+		SLOT.set(generator, '[[GeneratorContext]]', null); // step 3.b
+		state = 'COMPLETED'; // step 3.c
+	}
+
+	var value = abruptCompletion.value();
+
+	if (state === 'COMPLETED') { // step 3
+		return CreateIteratorResultObject(value, true); // steps 3.a-b
+	}
+
+	if (state !== 'SUSPENDED-YIELD') {
+		throw new $TypeError('Assertion failed: generator state is unexpected: ' + state); // step 4
+	}
+	if (abruptCompletion.type() === 'return') {
+		// due to representing `GeneratorContext` as a function, we can't safely re-invoke it, so we can't support sending it a return completion
+		return CreateIteratorResultObject(SLOT.get(generator, '[[CloseIfAbrupt]]')(NormalCompletion(abruptCompletion.value())), true);
+	}
+
+	var genContext = SLOT.get(generator, '[[GeneratorContext]]'); // step 5
+
+	SLOT.set(generator, '[[GeneratorState]]', 'EXECUTING'); // step 8
+
+	var result = genContext(value); // steps 6-7, 8-11
+
+	return result; // step 12
+};