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/pathval/CHANGELOG.md

@@ -0,0 +1,18 @@
+
+0.1.1 / 2013-12-30 
+==================
+
+ * expose parse
+ * rename lib to index
+
+0.1.0 / 2013-12-28
+==================
+
+  * API BREAKING! `get` has been changed, see the README for migration path
+  * Add `set` method
+  * Start using simple-assert (closes #2)
+
+0.0.1 / 2013-11-24
+==================
+
+  * Initial implementation