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/css-tree/data/index.js

@@ -0,0 +1,34 @@
+var mdnProperties = require('mdn-data/css/properties.json');
+var mdnSyntaxes = require('mdn-data/css/syntaxes.json');
+var patch = require('./patch.json');
+
+function buildDictionary(dict, patchDict) {
+    var result = {};
+
+    // copy all syntaxes for an original dict
+    for (var key in dict) {
+        result[key] = dict[key].syntax;
+    }
+
+    // apply a patch
+    for (var key in patchDict) {
+        if (key in dict) {
+            if (patchDict[key].syntax) {
+                result[key] = patchDict[key].syntax;
+            } else {
+                delete result[key];
+            }
+        } else {
+            if (patchDict[key].syntax) {
+                result[key] = patchDict[key].syntax;
+            }
+        }
+    }
+
+    return result;
+}
+
+module.exports = {
+    properties: buildDictionary(mdnProperties, patch.properties),
+    types: buildDictionary(mdnSyntaxes, patch.syntaxes)
+};