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/is-binary-path/index.js

@@ -0,0 +1,7 @@
+'use strict';
+const path = require('path');
+const binaryExtensions = require('binary-extensions');
+
+const extensions = new Set(binaryExtensions);
+
+module.exports = filePath => extensions.has(path.extname(filePath).slice(1).toLowerCase());