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/dotenv/config.js

@@ -0,0 +1,11 @@
+/* @flow */
+
+(function () {
+  require('./lib/main').config(
+    Object.assign(
+      {},
+      require('./lib/env-options'),
+      require('./lib/cli-options')(process.argv)
+    )
+  )
+})()