convert-blazor-server-to-webapp

Update the TFM to net8.0, replace AddServerSideBlazor with AddRazorComponents().AddInteractiveServerComponents(), replace MapBlazorHub with MapRazorComponents<App>().AddInteractiveServerRenderMode(), move the Router from App.razor into Routes.razor, and transform _Host.cshtml into an App.razor root component.

Move the HTML shell from Pages/_Host.cshtml into App.razor, remove Razor Page directives and Tag Helpers, replace the Component Tag Helpers with <HeadOutlet @rendermode="InteractiveServer" /> and <Routes @rendermode="InteractiveServer" />, change blazor.server.js to blazor.web.js, then delete _Host.cshtml.

The antiforgery middleware is missing from the pipeline. AddRazorComponents registers antiforgery services automatically, but you must explicitly add app.UseAntiforgery() after UseAuthentication and UseAuthorization, otherwise form POST requests fail with 400 errors.

The <CascadingAuthenticationState> component wrapper does not work across render mode boundaries in Blazor Web Apps. Replace it with builder.Services.AddCascadingAuthenticationState() in Program.cs, which provides the authentication state as a cascading value to all components.

Skip conversion if the app already uses AddRazorComponents and MapRazorComponents, if it is a Blazor WebAssembly app with a different migration path, if it should remain on the legacy Blazor Server hosting model, or if it still targets .NET Framework.