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/tinypool/dist/esm/entry/utils.js

@@ -0,0 +1,10 @@
+"use strict";
+import {
+  getHandler,
+  throwInNextTick
+} from "../chunk-DSRZHYCS.js";
+import "../chunk-T6A5DJAH.js";
+export {
+  getHandler,
+  throwInNextTick
+};