Auto generate installation instructions for packages

Rather than manually adding:

```
dotnet add package {package}
```

we could autogenerate this as part of the Update-Snippets, or at least validate that it is correct as part of CI. This would ensure that the value matches the library name and the --prerelease flag is only included for beta versions in libraries that have never GA'ed.

Start by locating the Update-Snippets workflow and the relevant CI checks. Determine how package names, library GA status, and beta versions are represented, then ensure generated or validated dotnet add package commands use the correct name and only add --prerelease when appropriate.

Written by the indexing model from the issue text.