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/loupe/lib/arguments.js

@@ -0,0 +1,7 @@
+import { inspectList } from './helpers'
+
+export default function inspectArguments(args, options) {
+  if (args.length === 0) return 'Arguments[]'
+  options.truncate -= 13
+  return `Arguments[ ${inspectList(args, options)} ]`
+}