Integrate React Query for data management and enhance Debug Preferences

- Added React Query for managing API calls related to assistants and voices.
- Introduced `useAssistantsQuery` and `useVoicesQuery` hooks for fetching data.
- Implemented mutations for creating, updating, and deleting voices using React Query.
- Integrated a global `QueryClient` for managing query states and configurations.
- Refactored components to utilize the new query hooks, improving data handling and performance.
- Added a Zustand store for managing debug preferences, including WebSocket URL and audio settings.

web/services/queryClient.ts

@@ -0,0 +1,12 @@
+import { QueryClient } from '@tanstack/react-query';
+
+export const queryClient = new QueryClient({
+  defaultOptions: {
+    queries: {
+      staleTime: 30_000,
+      gcTime: 5 * 60_000,
+      retry: 1,
+      refetchOnWindowFocus: false,
+    },
+  },
+});