Refactor EnvelopeStatus usage and streamline code

- Added `EnvelopeGenerator.Domain.Constants` in multiple files, replacing `Domain.Constants.EnvelopeStatus` with `EnvelopeStatus` for improved readability.
- Modified `CreateEnvelopeCommandHandler.cs` to directly use `request.UserId`, eliminating unnecessary local variable assignment.
- Identified potential duplication in query logic within `ReceiverAlreadySignedQuery.cs`.
- Updated `IEnvelopeService`, `EnvelopeReceiverService`, and `EnvelopeService` to ensure consistent usage of the simplified `EnvelopeStatus`.
- Overall, these changes enhance code maintainability and clarity.

EnvelopeGenerator.Application/Services/EnvelopeService.cs

@@ -5,6 +5,7 @@ using EnvelopeGenerator.Application.Interfaces.Services;
 using EnvelopeGenerator.Application.Dto;
 using EnvelopeGenerator.Domain.Entities;
 using EnvelopeGenerator.Application.Interfaces.Repositories;
+using EnvelopeGenerator.Domain.Constants;
 
 namespace EnvelopeGenerator.Application.Services;
 
@@ -67,7 +68,7 @@ public class EnvelopeService : BasicCRUDService<IEnvelopeRepository, EnvelopeDto
     /// <param name="max_status"></param>
     /// <param name="ignore_statuses"></param>
     /// <returns></returns>
-    public async Task<DataResult<IEnumerable<EnvelopeDto>>> ReadByUserAsync(int userId, Domain.Constants.EnvelopeStatus? min_status = null, Domain.Constants.EnvelopeStatus? max_status = null, params Domain.Constants.EnvelopeStatus[] ignore_statuses)
+    public async Task<DataResult<IEnumerable<EnvelopeDto>>> ReadByUserAsync(int userId, EnvelopeStatus? min_status = null, EnvelopeStatus? max_status = null, params EnvelopeStatus[] ignore_statuses)
     {
         var users = await _repository.ReadByUserAsync(userId: userId, min_status: min_status, max_status: max_status, ignore_statuses: ignore_statuses);            
         var readDto = _mapper.Map<IEnumerable<EnvelopeDto>>(users);