feat(frontend): add API client, layout, and routing

- Create Axios-based API client with sources, jobs, and dashboard endpoints
- Add responsive Layout component with navigation sidebar
- Set up React Router with Dashboard, Backups, and Settings routes
- Configure TanStack Query provider with default options
- Use lucide-react for navigation icons

frontend/node_modules/@babel/runtime/helpers/esm/skipFirstGeneratorNext.js

@@ -0,0 +1,7 @@
+function _skipFirstGeneratorNext(t) {
+  return function () {
+    var r = t.apply(this, arguments);
+    return r.next(), r;
+  };
+}
+export { _skipFirstGeneratorNext as default };