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/smartphone.mjs

@@ -0,0 +1,24 @@
+/**
+ * lucide-react v0.0.1 - ISC
+ */
+
+import createLucideIcon from '../createLucideIcon.mjs';
+
+const Smartphone = createLucideIcon("Smartphone", [
+  [
+    "rect",
+    {
+      width: "14",
+      height: "20",
+      x: "5",
+      y: "2",
+      rx: "2",
+      ry: "2",
+      key: "1yt0o3"
+    }
+  ],
+  ["path", { d: "M12 18h.01", key: "mhygvu" }]
+]);
+
+export { Smartphone as default };
+//# sourceMappingURL=smartphone.mjs.map