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-range-requests/utils/calculateEffectiveBoundaries.d.ts

@@ -0,0 +1,16 @@
+import '../_version.js';
+/**
+ * @param {Blob} blob A source blob.
+ * @param {number} [start] The offset to use as the start of the
+ * slice.
+ * @param {number} [end] The offset to use as the end of the slice.
+ * @return {Object} An object with `start` and `end` properties, reflecting
+ * the effective boundaries to use given the size of the blob.
+ *
+ * @private
+ */
+declare function calculateEffectiveBoundaries(blob: Blob, start?: number, end?: number): {
+    start: number;
+    end: number;
+};
+export { calculateEffectiveBoundaries };