API proposal for NotFound related APIs

[javiercn]

+Microsoft.AspNetCore.Components.Routing.NotFoundEventArgs.NotFoundEventArgs(string! url) ->
void
+Microsoft.AspNetCore.Components.Routing.NotFoundEventArgs.Path.get -> string!
+Microsoft.AspNetCore.Components.Routing.IHostEnvironmentNavigationManager.Initialize(string!
baseUri, string! uri, System.Func<string!, System.Threading.Tasks.Task!>! onNavigateTo) -> void
+virtual Microsoft.AspNetCore.Components.RenderTree.Renderer.SignalRendererToFinishRendering()
-> void
+Microsoft.AspNetCore.Components.NavigationManager.OnNotFound ->
System.EventHandler<Microsoft.AspNetCore.Components.Routing.NotFoundEventArgs!>!
+Microsoft.AspNetCore.Components.NavigationManager.NotFound() -> void
+Microsoft.AspNetCore.Components.Routing.NotFoundEventArgs
+Microsoft.AspNetCore.Components.Routing.NotFoundEventArgs.NotFoundEventArgs() -> void
+++ b/src/Components/Components/src/PublicAPI.Unshipped.txt
+
+Microsoft.AspNetCore.Components.Routing.Router.NotFoundPage.get -> System.Type!
+Microsoft.AspNetCore.Components.Routing.Router.NotFoundPage.set -> void
+++ b/src/Middleware/Diagnostics/src/PublicAPI.Unshipped.txt
+Microsoft.AspNetCore.Builder.StatusCodePagesOptions.CreateScopeForErrors.get -> bool
+Microsoft.AspNetCore.Builder.StatusCodePagesOptions.CreateScopeForErrors.set -> void
+static
Microsoft.AspNetCore.Builder.StatusCodePagesExtensions.UseStatusCodePagesWithReExecute(this
Microsoft.AspNetCore.Builder.IApplicationBuilder! app, string! pathFormat, bool
createScopeForErrors, string? queryFormat = null) ->
Microsoft.AspNetCore.Builder.IApplicationBuilder!

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