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/pencil.mjs

@@ -0,0 +1,16 @@
+/**
+ * lucide-react v0.0.1 - ISC
+ */
+
+import createLucideIcon from '../createLucideIcon.mjs';
+
+const Pencil = createLucideIcon("Pencil", [
+  [
+    "path",
+    { d: "M17 3a2.85 2.83 0 1 1 4 4L7.5 20.5 2 22l1.5-5.5Z", key: "5qss01" }
+  ],
+  ["path", { d: "m15 5 4 4", key: "1mk7zo" }]
+]);
+
+export { Pencil as default };
+//# sourceMappingURL=pencil.mjs.map