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-precaching/getCacheKeyForURL.d.ts

@@ -0,0 +1,22 @@
+import './_version.js';
+/**
+ * Takes in a URL, and returns the corresponding URL that could be used to
+ * lookup the entry in the precache.
+ *
+ * If a relative URL is provided, the location of the service worker file will
+ * be used as the base.
+ *
+ * For precached entries without revision information, the cache key will be the
+ * same as the original URL.
+ *
+ * For precached entries with revision information, the cache key will be the
+ * original URL with the addition of a query parameter used for keeping track of
+ * the revision info.
+ *
+ * @param {string} url The URL whose cache key to look up.
+ * @return {string} The cache key that corresponds to that URL.
+ *
+ * @memberof workbox-precaching
+ */
+declare function getCacheKeyForURL(url: string): string | undefined;
+export { getCacheKeyForURL };