chore: Register API controllers in Program.cs

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CutList.Web/Program.cs

@@ -6,6 +6,7 @@ using Microsoft.EntityFrameworkCore;
 var builder = WebApplication.CreateBuilder(args);
 
 // Add services to the container.
+builder.Services.AddControllers();
 builder.Services.AddRazorComponents()
     .AddInteractiveServerComponents();
 
@@ -33,6 +34,7 @@ app.UseHttpsRedirection();
 app.UseStaticFiles();
 app.UseAntiforgery();
 
+app.MapControllers();
 app.MapRazorComponents<App>()
     .AddInteractiveServerRenderMode();