Remove DotNetHost, DotNetHostPolicy, and DotNetHostResolver packages

[elinor-fung]

These are old packages (just contain dotnet, hostpolicy, hostfxr) that we no longer need. We had been relying on them for publishing symbols, but with #91031, symbols should be in other packages now (checked the publishing assets/symbols build log), so we can remove these packages and associated infrastructure only used by them.

Fixes #35244

cc @ViktorHofer

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Issue Details

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These are old packages (just contain dotnet, hostpolicy, hostfxr) that we no longer need. We had been relying on them for publishing symbols, but with #91031, symbols should be in other packages now (checked the publishing assets/symbols build log), so we can remove these packages and associated infrastructure only used by them.

Fixes #35244

cc @ViktorHofer

Author:	elinor-fung
Assignees:	-
Labels:	area-Infrastructure-libraries
Milestone:	-

[jkoritzinsky]

🚀

[ViktorHofer]

That package is still needed, right? It would be amazing if we would convert it from a pkgproj to a normal .proj and use NuGet's Pack task, so that we can remove all the pkgproj infrastructure from src/installer/*. As part of that, we should probably also move the package wrapper project to the host directory.

pkgprojs are deprecated and we want to eventually remove all of them from dotnet/runtime.

[elinor-fung]

Yeah, this one has binaries folks would use for custom hosting scenarios. I imagine we could/should convert it - that said, I'm not familiar with the differences between pkgproj / regular NuGet Pack.

I think the pkgproj infrastructure in src/installer is also used by Microsoft.DotNet.ILCompiler though: https://github.com/dotnet/runtime/blob/76d17b25252ce14b7e36c2e6854fe416db60f5cf/src/installer/pkg/projects/Microsoft.DotNet.ILCompiler/Microsoft.DotNet.ILCompiler.pkgproj

[ViktorHofer]

So sweet!

[agocke]