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/react-hook-form/dist/utils/createSubject.d.ts

@@ -0,0 +1,15 @@
+import type { Noop } from '../types';
+export type Observer<T> = {
+    next: (value: T) => void;
+};
+export type Subscription = {
+    unsubscribe: Noop;
+};
+export type Subject<T> = {
+    readonly observers: Observer<T>[];
+    subscribe: (value: Observer<T>) => Subscription;
+    unsubscribe: Noop;
+} & Observer<T>;
+declare const _default: <T>() => Subject<T>;
+export default _default;
+//# sourceMappingURL=createSubject.d.ts.map