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/index.cjs

@@ -0,0 +1,14 @@
+'use strict';
+
+const create = require('./create.cjs');
+const lexer = require('./config/lexer.cjs');
+const parser = require('./config/parser.cjs');
+const walker = require('./config/walker.cjs');
+
+const syntax = create({
+    ...lexer,
+    ...parser,
+    ...walker
+});
+
+module.exports = syntax;