Add Root navigation property to ResultView with FK

Added OutRes? Root navigation property to ResultView, annotated with [ForeignKey("Id")], to establish an optional relationship to the OutRes entity. Also added the necessary using directive for DataAnnotations.Schema.

src/ReC.Domain/Entities/ResultView.cs

@@ -1,9 +1,14 @@
-namespace ReC.Domain.Entities;
+using System.ComponentModel.DataAnnotations.Schema;
+
+namespace ReC.Domain.Entities;
 
 public class ResultView
 {
     public long Id { get; set; }
 
+    [ForeignKey("Id")]
+    public OutRes? Root { get; set; }
+
     public long? ActionId { get; set; }
 
     public RecActionView? Action { get; set; }