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/klona/json/index.js

@@ -0,0 +1,30 @@
+function klona(val) {
+	var k, out, tmp;
+
+	if (Array.isArray(val)) {
+		out = Array(k=val.length);
+		while (k--) out[k] = (tmp=val[k]) && typeof tmp === 'object' ? klona(tmp) : tmp;
+		return out;
+	}
+
+	if (Object.prototype.toString.call(val) === '[object Object]') {
+		out = {}; // null
+		for (k in val) {
+			if (k === '__proto__') {
+				Object.defineProperty(out, k, {
+					value: klona(val[k]),
+					configurable: true,
+					enumerable: true,
+					writable: true,
+				});
+			} else {
+				out[k] = (tmp=val[k]) && typeof tmp === 'object' ? klona(tmp) : tmp;
+			}
+		}
+		return out;
+	}
+
+	return val;
+}
+
+exports.klona = klona;