[Blazor] Better diagnostics for running on WebAssembly.

[javiercn]

There are many cases where customers are confused with the current two project setup. Here are some examples:

• Component set to Auto or WebAssembly but defined on the server project.
• Service consumed by Auto or WebAssembly component but only registered on the server project.
• Page defined on the Server project when the app has "global" interactivity.

[gragra33]

Was discussed here: Clarify the names of the interactive render modes for Blazor and rationalize with the component tag helper #50636 and early signs of it being an issue here: #50712 and here: #50992 and maybe others. IMHO, better guidance is needed.

Thanks for contacting us.

We're moving this issue to the .NET 9 Planning milestone for future evaluation / consideration. We would like to keep this around to collect more feedback, which can help us with prioritizing this work. We will re-evaluate this issue, during our next planning meeting(s).
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