Blazor extensibility

Needlr does not currently ship a Blazor-specific integration package. Blazor applications can use the normal Needlr ASP.NET Core, hosting, and service-registration packages, but component rendering and component discovery remain Blazor concerns.

Services consumed by components are ordinary DI services and can participate in Needlr source generation. Needlr must not treat Razor components themselves as automatic services merely because they are concrete classes.

A future Blazor integration requires an explicit package boundary, trimming and render-mode coverage, documentation, and a clear distinction between service registration and component composition.