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

src/api/SIGCM2.Application/PuntosDeVenta/Create/CreatePuntoDeVentaCommandHandler.cs

@@ -0,0 +1,75 @@
+using System.Transactions;
+using SIGCM2.Application.Abstractions;
+using SIGCM2.Application.Abstractions.Persistence;
+using SIGCM2.Application.Audit;
+using SIGCM2.Domain.Entities;
+using SIGCM2.Domain.Exceptions;
+
+namespace SIGCM2.Application.PuntosDeVenta.Create;
+
+public sealed class CreatePuntoDeVentaCommandHandler : ICommandHandler<CreatePuntoDeVentaCommand, PuntoDeVentaCreatedDto>
+{
+    private readonly IPuntoDeVentaRepository _repo;
+    private readonly IMedioRepository _medioRepo;
+    private readonly IAuditLogger _audit;
+
+    public CreatePuntoDeVentaCommandHandler(
+        IPuntoDeVentaRepository repo,
+        IMedioRepository medioRepo,
+        IAuditLogger audit)
+    {
+        _repo = repo;
+        _medioRepo = medioRepo;
+        _audit = audit;
+    }
+
+    public async Task<PuntoDeVentaCreatedDto> Handle(CreatePuntoDeVentaCommand command)
+    {
+        // Validate medio exists and is active (REQ-PDV-001, -002)
+        var medio = await _medioRepo.GetByIdAsync(command.MedioId)
+            ?? throw new MedioNotFoundException(command.MedioId);
+
+        if (!medio.Activo)
+            throw new MedioInactivoException(medio.Id);
+
+        // Check uniqueness NumeroAFIP within Medio (REQ-PDV-003)
+        var exists = await _repo.ExistsByNumeroAFIPInMedioAsync(command.MedioId, command.NumeroAFIP, excludeId: null);
+        if (exists)
+            throw new NumeroAFIPDuplicadoException(command.MedioId, command.NumeroAFIP);
+
+        var pdv = PuntoDeVenta.ForCreation(command.MedioId, command.NumeroAFIP, command.Nombre, command.Descripcion);
+
+        using var tx = new TransactionScope(
+            TransactionScopeOption.Required,
+            new TransactionOptions { IsolationLevel = System.Transactions.IsolationLevel.ReadCommitted },
+            TransactionScopeAsyncFlowOption.Enabled);
+
+        var newId = await _repo.AddAsync(pdv);
+
+        // fail-closed: if LogAsync throws, tx rolls back (REQ-PDV-010)
+        await _audit.LogAsync(
+            action: "punto_de_venta.create",
+            targetType: "PuntoDeVenta",
+            targetId: newId.ToString(),
+            metadata: new
+            {
+                after = new
+                {
+                    pdv.MedioId,
+                    pdv.NumeroAFIP,
+                    pdv.Nombre,
+                    pdv.Descripcion,
+                },
+            });
+
+        tx.Complete();
+
+        return new PuntoDeVentaCreatedDto(
+            Id: newId,
+            MedioId: pdv.MedioId,
+            NumeroAFIP: pdv.NumeroAFIP,
+            Nombre: pdv.Nombre,
+            Descripcion: pdv.Descripcion,
+            Activo: pdv.Activo);
+    }
+}