Async callbacks for `success` and `error` in toast.promise

[Specy]

Sometimes to show an error or success dialog we need to fetch additional data, for example, when the api i want to fetch data from returns an error code and i need to fetch the text of the error code before showing it. example:

toast.promise(somePromise, {
    loading: "Saving data:...", 
    success: "Data saved!",
    error: async (e) => `There was an error: ${await getErrorMessage(e)}`
})

[MilosMosovsky]

+1