Update article for Blazor Web App template

[PetiaVladova]

With 2024 Q2 the Visual Studio extension is updated, so Blazor item templates are fully functional in the new Blazor Web App template.
https://github.com/telerik/vsx/issues/772
In summary changes are the following:

• webReportDesigner.html file is added when we are using HTML5 designer item template. For Blazor item templates we add razor pages
• Sample report and ReportController are added only when the REST service is new. The existing logic is expected to stay unmodified (No changes required)
• App.razor changes are added both for new and existing service, in all interactive render modes and interactivity locations
• Render mode attribute is added when the interactivity location is per Page or when the interactive render mode is None