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/isNativeReflectConstruct.js

@@ -0,0 +1,9 @@
+function _isNativeReflectConstruct() {
+  try {
+    var t = !Boolean.prototype.valueOf.call(Reflect.construct(Boolean, [], function () {}));
+  } catch (t) {}
+  return (_isNativeReflectConstruct = function _isNativeReflectConstruct() {
+    return !!t;
+  })();
+}
+export { _isNativeReflectConstruct as default };