feat(application): repository abstraction + DTOs + validators + handlers CRUD PuntosDeVenta con auditoría + retry deadlock

tests/SIGCM2.Application.Tests/PuntosDeVenta/GetById/GetPuntoDeVentaByIdQueryHandlerTests.cs

@@ -0,0 +1,46 @@
+using NSubstitute;
+using SIGCM2.Application.Abstractions.Persistence;
+using SIGCM2.Application.PuntosDeVenta.GetById;
+using SIGCM2.Domain.Entities;
+using SIGCM2.Domain.Exceptions;
+
+namespace SIGCM2.Application.Tests.PuntosDeVenta.GetById;
+
+public class GetPuntoDeVentaByIdQueryHandlerTests
+{
+    private readonly IPuntoDeVentaRepository _repo = Substitute.For<IPuntoDeVentaRepository>();
+    private readonly GetPuntoDeVentaByIdQueryHandler _handler;
+
+    public GetPuntoDeVentaByIdQueryHandlerTests()
+    {
+        _handler = new GetPuntoDeVentaByIdQueryHandler(_repo);
+    }
+
+    private static PuntoDeVenta MakePdv(int id = 5) =>
+        new(id, 2, 3, "PdV " + id, "Desc", true, DateTime.UtcNow, null);
+
+    [Fact]
+    public async Task Handle_NotFound_ThrowsPuntoDeVentaNotFoundException()
+    {
+        _repo.GetByIdAsync(999, Arg.Any<CancellationToken>()).Returns((PuntoDeVenta?)null);
+
+        await Assert.ThrowsAsync<PuntoDeVentaNotFoundException>(
+            () => _handler.Handle(new GetPuntoDeVentaByIdQuery(999)));
+    }
+
+    [Fact]
+    public async Task Handle_HappyPath_ReturnsDtoWithCorrectFields()
+    {
+        var pdv = MakePdv(5);
+        _repo.GetByIdAsync(5, Arg.Any<CancellationToken>()).Returns(pdv);
+
+        var result = await _handler.Handle(new GetPuntoDeVentaByIdQuery(5));
+
+        Assert.Equal(5, result.Id);
+        Assert.Equal(2, result.MedioId);
+        Assert.Equal(3, result.NumeroAFIP);
+        Assert.Equal("PdV 5", result.Nombre);
+        Assert.Equal("Desc", result.Descripcion);
+        Assert.True(result.Activo);
+    }
+}