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

src/api/SIGCM2.Application/Common/PuntosDeVentaQuery.cs

@@ -0,0 +1,9 @@
+namespace SIGCM2.Application.Common;
+
+/// <summary>Query parameters for listing puntos de venta with optional filters and paging.</summary>
+public sealed record PuntosDeVentaQuery(
+    int Page,
+    int PageSize,
+    int? MedioId,
+    bool? Activo
+);