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/arrayLikeToArray.js

@@ -0,0 +1,6 @@
+function _arrayLikeToArray(r, a) {
+  (null == a || a > r.length) && (a = r.length);
+  for (var e = 0, n = Array(a); e < a; e++) n[e] = r[e];
+  return n;
+}
+module.exports = _arrayLikeToArray, module.exports.__esModule = true, module.exports["default"] = module.exports;