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/database-backup.js

@@ -0,0 +1,26 @@
+/**
+ * @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 DatabaseBackup = createLucideIcon("DatabaseBackup", [
+  ["ellipse", { cx: "12", cy: "5", rx: "9", ry: "3", key: "msslwz" }],
+  ["path", { d: "M3 12a9 3 0 0 0 5 2.69", key: "1ui2ym" }],
+  ["path", { d: "M21 9.3V5", key: "6k6cib" }],
+  ["path", { d: "M3 5v14a9 3 0 0 0 6.47 2.88", key: "i62tjy" }],
+  ["path", { d: "M12 12v4h4", key: "1bxaet" }],
+  [
+    "path",
+    {
+      d: "M13 20a5 5 0 0 0 9-3 4.5 4.5 0 0 0-4.5-4.5c-1.33 0-2.54.54-3.41 1.41L12 16",
+      key: "1f4ei9"
+    }
+  ]
+]);
+
+export { DatabaseBackup as default };
+//# sourceMappingURL=database-backup.js.map