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/zap-off.js

@@ -0,0 +1,18 @@
+/**
+ * @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 ZapOff = createLucideIcon("ZapOff", [
+  ["polyline", { points: "12.41 6.75 13 2 10.57 4.92", key: "122m05" }],
+  ["polyline", { points: "18.57 12.91 21 10 15.66 10", key: "16r43o" }],
+  ["polyline", { points: "8 8 3 14 12 14 11 22 16 16", key: "tmh4bc" }],
+  ["line", { x1: "2", x2: "22", y1: "2", y2: "22", key: "a6p6uj" }]
+]);
+
+export { ZapOff as default };
+//# sourceMappingURL=zap-off.js.map