Add an analyzer to warn about code that runs after calling NavigationManager.NavigateTo in server side contexts

We used to throw a navigation exception and that would stop the execution. this was unique on an SSR context and we switched to just signal the navigation and stop the rendering after the current render batch.

As a result, code that was after the NavigateTo instruction wouldn't run, and now it does, and apps need to be aware of that.

Connected report: https://github.com/dotnet/AspNetCore.Docs/issues/37581

Start by reading the issue's description of NavigationManager.NavigateTo behavior in server-side contexts and review the connected ASP.NET Core Docs report. The work is done when an analyzer warns about code after NavigateTo in the affected contexts and the warning behavior is covered as appropriate by the project.

Written by the indexing model from the issue text.