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/message-circle-code.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 MessageCircleCode = createLucideIcon("MessageCircleCode", [
+  ["path", { d: "M7.9 20A9 9 0 1 0 4 16.1L2 22Z", key: "vv11sd" }],
+  ["path", { d: "m10 10-2 2 2 2", key: "p6et6i" }],
+  ["path", { d: "m14 10 2 2-2 2", key: "1kkmpt" }]
+]);
+
+export { MessageCircleCode as default };
+//# sourceMappingURL=message-circle-code.js.map