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/ampersands.js

@@ -0,0 +1,28 @@
+/**
+ * @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 Ampersands = createLucideIcon("Ampersands", [
+  [
+    "path",
+    {
+      d: "M10 17c-5-3-7-7-7-9a2 2 0 0 1 4 0c0 2.5-5 2.5-5 6 0 1.7 1.3 3 3 3 2.8 0 5-2.2 5-5",
+      key: "12lh1k"
+    }
+  ],
+  [
+    "path",
+    {
+      d: "M22 17c-5-3-7-7-7-9a2 2 0 0 1 4 0c0 2.5-5 2.5-5 6 0 1.7 1.3 3 3 3 2.8 0 5-2.2 5-5",
+      key: "173c68"
+    }
+  ]
+]);
+
+export { Ampersands as default };
+//# sourceMappingURL=ampersands.js.map