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/lodash/_baseProperty.js

@@ -0,0 +1,14 @@
+/**
+ * The base implementation of `_.property` without support for deep paths.
+ *
+ * @private
+ * @param {string} key The key of the property to get.
+ * @returns {Function} Returns the new accessor function.
+ */
+function baseProperty(key) {
+  return function(object) {
+    return object == null ? undefined : object[key];
+  };
+}
+
+module.exports = baseProperty;