refactor: migrate from @hey-api/openapi-ts to openapi-react-query

- Replace @hey-api/openapi-ts with openapi-typescript and openapi-react-query
- Generate TypeScript types from OpenAPI spec
- Set up React Query infrastructure with QueryClientProvider
- Migrate all API hooks to use React Query patterns
- Maintain backward compatibility for existing components
- Remove old API infrastructure and dependencies

www/app/lib/queryClient.tsx

@@ -0,0 +1,17 @@
+"use client";
+
+import { QueryClient } from "@tanstack/react-query";
+
+export const queryClient = new QueryClient({
+  defaultOptions: {
+    queries: {
+      staleTime: 60 * 1000, // 1 minute
+      gcTime: 5 * 60 * 1000, // 5 minutes (formerly cacheTime)
+      retry: 1,
+      refetchOnWindowFocus: false,
+    },
+    mutations: {
+      retry: 0,
+    },
+  },
+});