Refactor SQL execution and enhance envelope creation

- Updated `ISQLExecutor<TEntity>` to inherit from new `ISQLExecutor` interface for improved SQL execution flexibility.
- Added package references for `Dapper` and `DigitalData.Core` in project files.
- Modified `CreateEnvelopeCommand` to include `[BindNever]` on `UserId` for better model binding control.
- Refactored `CreateEnvelopeCommandHandler` to use `DynamicParameters` for SQL parameter handling.
- Updated `CreateEnvelopeSQL` to select only the top record for performance.
- Introduced `GetIdOrDefault` method in `ControllerExtensions` for user ID retrieval with fallback.
- Added `CreateAsync` method in `EnvelopeController` for envelope creation using `IMediator`.
- Ensured infrastructure project has necessary package references.
- Refactored `SQLExecutor` to implement new interface and simplified constructor.
- Introduced `SQLExecutorBaseEntity` for entity-specific SQL command execution.

EnvelopeGenerator.Application/Envelopes/Commands/CreateEnvelopeCommand.cs

@@ -1,4 +1,5 @@
 using MediatR;
+using Microsoft.AspNetCore.Mvc.ModelBinding;
 using System.ComponentModel.DataAnnotations;
 using System.Text.Json.Serialization;
 
@@ -20,5 +21,6 @@ public record CreateEnvelopeCommand(
     /// Id of receiver
     /// </summary>
     [JsonIgnore]
+    [BindNever]
     public int? UserId { get; set; }
 };