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/_basePropertyDeep.js

@@ -0,0 +1,16 @@
+var baseGet = require('./_baseGet');
+
+/**
+ * A specialized version of `baseProperty` which supports deep paths.
+ *
+ * @private
+ * @param {Array|string} path The path of the property to get.
+ * @returns {Function} Returns the new accessor function.
+ */
+function basePropertyDeep(path) {
+  return function(object) {
+    return baseGet(object, path);
+  };
+}
+
+module.exports = basePropertyDeep;