Move InsertObjectResult mapping to Fluent API

Removed [Column] attribute from InsertObjectResult and configured column mapping for NewObjectId in RecDbContext using the Fluent API. This centralizes entity mapping logic in the DbContext.

src/ReC.Domain/QueryOutput/InsertObjectResult.cs

@@ -4,6 +4,5 @@ namespace ReC.Domain.QueryOutput;
 
 public class InsertObjectResult
 {
-    [Column("oGUID")]
     public required long NewObjectId { get; set; }
 }

src/ReC.Infrastructure/RecDbContext.cs

@@ -314,5 +314,10 @@ public class RecDbContext(DbContextOptions<RecDbContext> options) : DbContext(op
             b.Property(e => e.RawBody).HasColumnName("REQUEST_BODY");
         });
 
+        modelBuilder.Entity<InsertObjectResult>(b =>
+        {
+            b.HasNoKey();
+            b.Property(e => e.NewObjectId).HasColumnName("oGUID");
+        });
     }
 }