bdf2527fc1
- Updated `using` directives in `Config.cs` and `EnvelopeType.cs` to include additional namespaces and removed `DigitalData.Core.Abstractions`. - Adjusted formatting for `StatusName` and `IsAlreadySent` properties in `Envelope.cs` for consistency. - Simplified `User` property in `Envelope.cs` by removing the namespace prefix. - Introduced a new `User` class in `User.cs` with various properties and data annotations for database mapping. - Removed the `<Nullable>` property from `EnvelopeGenerator.Domain.csproj`, which may impact nullability handling.