Add endpoint metadata to developer exception page (#52668)

Author: Kahbazi

src/Middleware/Diagnostics/src/DeveloperExceptionPage/DeveloperExceptionPageMiddlewareImpl.cs

@@ -320,8 +320,11 @@ private Task DisplayRuntimeException(HttpContext context, Exception ex)
         EndpointModel? endpointModel = null;
         if (endpoint != null)
         {
-            endpointModel = new EndpointModel();
-            endpointModel.DisplayName = endpoint.DisplayName;
+            endpointModel = new EndpointModel
+            {
+                DisplayName = endpoint.DisplayName,
+                Metadata = endpoint.Metadata
+            };
 
             if (endpoint is RouteEndpoint routeEndpoint)
             {

src/Middleware/Diagnostics/src/DeveloperExceptionPage/Views/EndpointModel.cs

@@ -1,6 +1,8 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using Microsoft.AspNetCore.Http;
+
 namespace Microsoft.AspNetCore.Diagnostics.RazorViews;
 
 internal sealed class EndpointModel
@@ -9,4 +11,5 @@ internal sealed class EndpointModel
     public string? RoutePattern { get; set; }
     public int? Order { get; set; }
     public string? HttpMethods { get; set; }
+    public EndpointMetadataCollection? Metadata { get; set; }
 }