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/lib/syntax/config/parser.js

@@ -0,0 +1,30 @@
+import * as scope from '../scope/index.js';
+import atrule from '../atrule/index.js';
+import pseudo from '../pseudo/index.js';
+import * as node from '../node/index-parse.js';
+
+export default {
+    parseContext: {
+        default: 'StyleSheet',
+        stylesheet: 'StyleSheet',
+        atrule: 'Atrule',
+        atrulePrelude(options) {
+            return this.AtrulePrelude(options.atrule ? String(options.atrule) : null);
+        },
+        mediaQueryList: 'MediaQueryList',
+        mediaQuery: 'MediaQuery',
+        rule: 'Rule',
+        selectorList: 'SelectorList',
+        selector: 'Selector',
+        block() {
+            return this.Block(true);
+        },
+        declarationList: 'DeclarationList',
+        declaration: 'Declaration',
+        value: 'Value'
+    },
+    scope,
+    atrule,
+    pseudo,
+    node
+};