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/slash/index.js

@@ -0,0 +1,11 @@
+'use strict';
+module.exports = path => {
+	const isExtendedLengthPath = /^\\\\\?\\/.test(path);
+	const hasNonAscii = /[^\u0000-\u0080]+/.test(path); // eslint-disable-line no-control-regex
+
+	if (isExtendedLengthPath || hasNonAscii) {
+		return path;
+	}
+
+	return path.replace(/\\/g, '/');
+};