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/fast-glob/out/utils/string.js

@@ -0,0 +1,11 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.isEmpty = exports.isString = void 0;
+function isString(input) {
+    return typeof input === 'string';
+}
+exports.isString = isString;
+function isEmpty(input) {
+    return input === '';
+}
+exports.isEmpty = isEmpty;