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/workbox-core/skipWaiting.js

@@ -0,0 +1,27 @@
+/*
+  Copyright 2019 Google LLC
+
+  Use of this source code is governed by an MIT-style
+  license that can be found in the LICENSE file or at
+  https://opensource.org/licenses/MIT.
+*/
+import { logger } from './_private/logger.js';
+import './_version.js';
+/**
+ * This method is deprecated, and will be removed in Workbox v7.
+ *
+ * Calling self.skipWaiting() is equivalent, and should be used instead.
+ *
+ * @memberof workbox-core
+ */
+function skipWaiting() {
+    // Just call self.skipWaiting() directly.
+    // See https://github.com/GoogleChrome/workbox/issues/2525
+    if (process.env.NODE_ENV !== 'production') {
+        logger.warn(`skipWaiting() from workbox-core is no longer recommended ` +
+            `and will be removed in Workbox v7. Using self.skipWaiting() instead ` +
+            `is equivalent.`);
+    }
+    void self.skipWaiting();
+}
+export { skipWaiting };