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/css-tree/cjs/definition-syntax/index.cjs

@@ -0,0 +1,13 @@
+'use strict';
+
+const SyntaxError = require('./SyntaxError.cjs');
+const generate = require('./generate.cjs');
+const parse = require('./parse.cjs');
+const walk = require('./walk.cjs');
+
+
+
+exports.SyntaxError = SyntaxError.SyntaxError;
+exports.generate = generate.generate;
+exports.parse = parse.parse;
+exports.walk = walk.walk;