feat(aspnetcore): auto-register IExceptionHandler in WebApplicationBuilder.AddExceptionless

AddExceptionless() on WebApplicationBuilder now automatically calls
AddExceptionlessExceptionHandler(), eliminating the need for a separate
registration call. The standalone AddExceptionlessExceptionHandler()
method remains public for non-WebApplicationBuilder scenarios.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: niemyjski

samples/Exceptionless.SampleAspNetCore/Program.cs

@@ -10,15 +10,15 @@
 builder.Logging.AddExceptionless();
 
 // Reads settings from IConfiguration then adds additional configuration from this lambda.
-// This also configures ExceptionlessClient.Default and host shutdown queue flushing.
+// This also configures ExceptionlessClient.Default, host shutdown queue flushing,
+// and automatically registers the Exceptionless IExceptionHandler.
 builder.AddExceptionless(c => c.DefaultData["Startup"] = "heyyy");
 // OR
 // builder.AddExceptionless();
 // OR
 // builder.AddExceptionless("API_KEY_HERE");
 
-// Adds ASP.NET Core request/unhandled exception hooks and standard exception handling services.
-builder.Services.AddExceptionlessExceptionHandler();
+// Required: configures the response format for unhandled exceptions (e.g., RFC 7807 Problem Details).
 builder.Services.AddProblemDetails();
 
 // This is normal ASP.NET Core code.

src/Platforms/Exceptionless.AspNetCore/ExceptionlessExtensions.cs

@@ -14,9 +14,40 @@
 
 namespace Exceptionless {
     public static class ExceptionlessExtensions {
+        /// <summary>
+        /// Adds the given pre-configured <see cref="ExceptionlessClient"/> to the web application builder,
+        /// registers lifecycle hooks, and automatically registers the Exceptionless <see cref="IExceptionHandler"/>.
+        /// </summary>
+        public static WebApplicationBuilder AddExceptionless(this WebApplicationBuilder builder, ExceptionlessClient client) {
+            ((IHostApplicationBuilder)builder).AddExceptionless(client);
+            builder.Services.AddExceptionlessExceptionHandler();
+            return builder;
+        }
+
+        /// <summary>
+        /// Adds an <see cref="ExceptionlessClient"/> to the web application builder using the specified API key,
+        /// registers lifecycle hooks, and automatically registers the Exceptionless <see cref="IExceptionHandler"/>.
+        /// </summary>
+        public static WebApplicationBuilder AddExceptionless(this WebApplicationBuilder builder, string apiKey) {
+            ((IHostApplicationBuilder)builder).AddExceptionless(apiKey);
+            builder.Services.AddExceptionlessExceptionHandler();
+            return builder;
+        }
+
+        /// <summary>
+        /// Adds an <see cref="ExceptionlessClient"/> to the web application builder using configuration,
+        /// registers lifecycle hooks, and automatically registers the Exceptionless <see cref="IExceptionHandler"/>.
+        /// </summary>
+        public static WebApplicationBuilder AddExceptionless(this WebApplicationBuilder builder, Action<ExceptionlessConfiguration> configure = null) {
+            ((IHostApplicationBuilder)builder).AddExceptionless(configure);
+            builder.Services.AddExceptionlessExceptionHandler();
+            return builder;
+        }
+
         /// <summary>
         /// Registers the Exceptionless <see cref="IExceptionHandler"/> and required ASP.NET Core services
         /// for capturing unhandled exceptions. Call this in your service configuration alongside <c>app.UseExceptionHandler()</c>.
+        /// This is called automatically when using the <see cref="WebApplicationBuilder"/> overloads of <c>AddExceptionless</c>.
         /// </summary>
         public static IServiceCollection AddExceptionlessExceptionHandler(this IServiceCollection services) {
             services.AddHttpContextAccessor();

src/Platforms/Exceptionless.AspNetCore/readme.txt

@@ -32,16 +32,16 @@ using Exceptionless;
 
 var builder = WebApplication.CreateBuilder(args); 
 builder.AddExceptionless(c => c.ApiKey = "API_KEY_HERE");
-builder.Services.AddExceptionlessExceptionHandler();
 builder.Services.AddProblemDetails();
 
-In order to start gathering unhandled exceptions, you will need to register the Exceptionless middleware in your application 
-like this after building your application:
-
 var app = builder.Build(); 
 app.UseExceptionHandler();
 app.UseExceptionless();
 
+The `AddExceptionless` call on `WebApplicationBuilder` automatically registers the Exceptionless IExceptionHandler 
+for capturing unhandled exceptions. You still need `AddProblemDetails()` (or your own handler) to produce the HTTP 
+error response, and `UseExceptionHandler()` to enable the exception handling pipeline.
+
 Alternatively, you can use different overloads of the host builder AddExceptionless method for other configuration options.
 Please visit the documentation at https://exceptionless.com/docs/clients/dotnet/sending-events/ for additional examples 
 and guidance on sending events to Exceptionless.