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/postcss-replace-overflow-wrap/index.js

@@ -0,0 +1,19 @@
+// @ts-check
+
+module.exports = function (opts) {
+    opts = opts || {}
+    var method = opts.method || 'replace'
+    return {
+        postcssPlugin: 'postcss-replace-overflow-wrap',
+        Declaration: {
+            'overflow-wrap': decl => {
+                decl.cloneBefore({ prop: 'word-wrap' })
+                if (method === 'replace') {
+                    decl.remove()
+                }
+            }
+        }
+    }
+}
+
+module.exports.postcss = true