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/strip-indent/index.js

@@ -0,0 +1,14 @@
+'use strict';
+const minIndent = require('min-indent');
+
+module.exports = string => {
+	const indent = minIndent(string);
+
+	if (indent === 0) {
+		return string;
+	}
+
+	const regex = new RegExp(`^[ \\t]{${indent}}`, 'gm');
+
+	return string.replace(regex, '');
+};