feat: return organisationId if user is an organization

this will help to determine if an event is created by the user or not

WebApp/DTOs/UserSummaryDto.cs

@@ -11,4 +11,15 @@ namespace WebApp.DTOs
         [Required] DateTime CreatedAt,
         [Required] bool isOrganisation
     );
+
+    public record class UserSummaryWithOrgIdDto
+    (
+        [Required] int UserId,
+        [Required] string Email,
+        [Required] string FirstName,
+        [Required] string LastName,
+        [Required] DateTime CreatedAt,
+        [Required] bool isOrganisation,
+        int? OrganisationId
+    );
 }