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/deep-equal/example/cmp.js

@@ -0,0 +1,13 @@
+'use strict';
+
+var equal = require('../');
+console.dir([
+  equal(
+    { a: [2, 3], b: [4] },
+    { a: [2, 3], b: [4] }
+  ),
+  equal(
+    { x: 5, y: [6] },
+    { x: 5, y: 6 }
+  )
+]);