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/lucide-react/dist/esm/icons/codepen.mjs

@@ -0,0 +1,19 @@
+/**
+ * lucide-react v0.0.1 - ISC
+ */
+
+import createLucideIcon from '../createLucideIcon.mjs';
+
+const Codepen = createLucideIcon("Codepen", [
+  [
+    "polygon",
+    { points: "12 2 22 8.5 22 15.5 12 22 2 15.5 2 8.5 12 2", key: "srzb37" }
+  ],
+  ["line", { x1: "12", x2: "12", y1: "22", y2: "15.5", key: "1t73f2" }],
+  ["polyline", { points: "22 8.5 12 15.5 2 8.5", key: "ajlxae" }],
+  ["polyline", { points: "2 15.5 12 8.5 22 15.5", key: "susrui" }],
+  ["line", { x1: "12", x2: "12", y1: "2", y2: "8.5", key: "2cldga" }]
+]);
+
+export { Codepen as default };
+//# sourceMappingURL=codepen.mjs.map