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/cable.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 Cable = createLucideIcon("Cable", [
+  ["path", { d: "M4 9a2 2 0 0 1-2-2V5h6v2a2 2 0 0 1-2 2Z", key: "1s6oa5" }],
+  ["path", { d: "M3 5V3", key: "1k5hjh" }],
+  ["path", { d: "M7 5V3", key: "1t1388" }],
+  ["path", { d: "M19 15V6.5a3.5 3.5 0 0 0-7 0v11a3.5 3.5 0 0 1-7 0V9", key: "1ytv72" }],
+  ["path", { d: "M17 21v-2", key: "ds4u3f" }],
+  ["path", { d: "M21 21v-2", key: "eo0ou" }],
+  ["path", { d: "M22 19h-6v-2a2 2 0 0 1 2-2h2a2 2 0 0 1 2 2Z", key: "sdz6o8" }]
+]);
+
+export { Cable as default };
+//# sourceMappingURL=cable.js.map