Added FirstAsync<T, TException> as an obsolete extension method for Task<IEnumerable<T>>. This method returns the first element or throws a custom exception if the result is null, using a provided factory delegate. Intended for legacy .NET projects.
Added FirstAsync<T, TException> as an obsolete extension method for Task<IEnumerable<T>>. This method returns the first element or throws a custom exception if the result is null, using a provided factory delegate. Intended for legacy .NET projects.