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/lamp-wall-down.js

@@ -0,0 +1,17 @@
+/**
+ * @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 LampWallDown = createLucideIcon("LampWallDown", [
+  ["path", { d: "M11 13h6l3 7H8l3-7Z", key: "9n3qlo" }],
+  ["path", { d: "M14 13V8a2 2 0 0 0-2-2H8", key: "1hu4hb" }],
+  ["path", { d: "M4 9h2a2 2 0 0 0 2-2V5a2 2 0 0 0-2-2H4v6Z", key: "s053bc" }]
+]);
+
+export { LampWallDown as default };
+//# sourceMappingURL=lamp-wall-down.js.map