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/_defineProperty.js

@@ -0,0 +1,11 @@
+var getNative = require('./_getNative');
+
+var defineProperty = (function() {
+  try {
+    var func = getNative(Object, 'defineProperty');
+    func({}, '', {});
+    return func;
+  } catch (e) {}
+}());
+
+module.exports = defineProperty;