Add ConfigureRouteHandlerJsonOptions for M.A.Htt.Json.JsonOptions (#39502)

* Add ConfigureHttpJsonOptions for M.A.Htt.Json.JsonOptions

* Address initial feedback from API review

* Fix method reference in doc comment

* Fix up crefs

src/Http/Http.Extensions/src/HttpJsonServiceExtensions.cs

+// 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.Json;
+
+namespace Microsoft.Extensions.DependencyInjection;
+
+/// <summary>
+/// Extension methods to configure JSON serialization behavior.
+/// </summary>
+public static class RouteHandlerJsonServiceExtensions
+{
+    /// <summary>
+    /// Configures options used for reading and writing JSON by route handlers.
+    /// </summary>
+    /// <remarks>
+    /// The options configured here will only affect JSON returned and processed
+    /// from route handlers, not controllers, when using <see cref="O:Microsoft.AspNetCore.Http.HttpRequestJsonExtensions.ReadFromJsonAsync" />
+    /// and <see cref="O:Microsoft.AspNetCore.Http.HttpResponseJsonExtensions.WriteAsJsonAsync" />.
+    /// </remarks>
+    /// <param name="services">The <see cref="IServiceCollection" /> to configure options on.</param>
+    /// <param name="configureOptions">The <see cref="Action{JsonOptions}"/> to configure the
+    /// <see cref="JsonOptions"/>.</param>
+    /// <returns>The modified <see cref="IServiceCollection"/>.</returns>
+    public static IServiceCollection ConfigureRouteHandlerJsonOptions(this IServiceCollection services, Action<JsonOptions> configureOptions)
+    {
+        services.Configure<JsonOptions>(configureOptions);
+        return services;
+    }
+}

src/Http/Http.Extensions/src/PublicAPI.Unshipped.txt

 #nullable enable
+Microsoft.Extensions.DependencyInjection.RouteHandlerJsonServiceExtensions
+static Microsoft.Extensions.DependencyInjection.RouteHandlerJsonServiceExtensions.ConfigureRouteHandlerJsonOptions(this Microsoft.Extensions.DependencyInjection.IServiceCollection! services, System.Action<Microsoft.AspNetCore.Http.Json.JsonOptions!>! configureOptions) -> Microsoft.Extensions.DependencyInjection.IServiceCollection!