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/syntax/atrule/index.cjs

@@ -0,0 +1,19 @@
+'use strict';
+
+const fontFace = require('./font-face.cjs');
+const _import = require('./import.cjs');
+const media = require('./media.cjs');
+const nest = require('./nest.cjs');
+const page = require('./page.cjs');
+const supports = require('./supports.cjs');
+
+const atrule = {
+    'font-face': fontFace,
+    'import': _import,
+    media,
+    nest,
+    page,
+    supports
+};
+
+module.exports = atrule;