Add envelope history tracking and receiver signing status

Added a `Histories` property to `EnvelopeDto` to track envelope
history entries for actions like `DocumentSigned` and
`EnvelopeOpened`. Introduced a computed `Signed` property in
`EnvelopeReceiverDto` to determine if a receiver has signed the
envelope based on the history. Updated `using` directives to
support these changes.

EnvelopeGenerator.Application/Common/Dto/EnvelopeDto.cs

@@ -1,6 +1,7 @@
 using DigitalData.EmailProfilerDispatcher.Abstraction.Attributes;
 using DigitalData.UserManager.Application.DTOs.User;
 using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiver;
+using EnvelopeGenerator.Application.Common.Dto.History;
 using EnvelopeGenerator.Domain.Constants;
 using EnvelopeGenerator.Domain.Entities;
 using EnvelopeGenerator.Domain.Interfaces;
@@ -129,4 +130,9 @@ public record EnvelopeDto : IEnvelope
     /// 
     /// </summary>
     public IEnumerable<EnvelopeReceiverDto>? EnvelopeReceivers { get; set; }
+
+    /// <summary>
+    /// Envelope history entries tracking actions like DocumentSigned, EnvelopeOpened, etc.
+    /// </summary>
+    public IEnumerable<HistoryDto>? Histories { get; set; }
 }