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/lucide-react/dist/esm/icons/refresh-cw-off.js

@@ -0,0 +1,21 @@
+/**
+ * @license lucide-react v0.303.0 - ISC
+ *
+ * This source code is licensed under the ISC license.
+ * See the LICENSE file in the root directory of this source tree.
+ */
+
+import createLucideIcon from '../createLucideIcon.js';
+
+const RefreshCwOff = createLucideIcon("RefreshCwOff", [
+  ["path", { d: "M21 8L18.74 5.74A9.75 9.75 0 0 0 12 3C11 3 10.03 3.16 9.13 3.47", key: "1krf6h" }],
+  ["path", { d: "M8 16H3v5", key: "1cv678" }],
+  ["path", { d: "M3 12C3 9.51 4 7.26 5.64 5.64", key: "ruvoct" }],
+  ["path", { d: "m3 16 2.26 2.26A9.75 9.75 0 0 0 12 21c2.49 0 4.74-1 6.36-2.64", key: "19q130" }],
+  ["path", { d: "M21 12c0 1-.16 1.97-.47 2.87", key: "4w8emr" }],
+  ["path", { d: "M21 3v5h-5", key: "1q7to0" }],
+  ["path", { d: "M22 22 2 2", key: "1r8tn9" }]
+]);
+
+export { RefreshCwOff as default };
+//# sourceMappingURL=refresh-cw-off.js.map