Fix building the host-targeting components and packing ILC

[jkoritzinsky]

NETCoreSdkRuntimeIdentifier isn't set until after the Microsoft.NET.Sdk's Sdk.props file has been imported fully. Use the "after Sdk props" hook to set the "should build host tools" property so project files and item groups in Subsets.props can see the correct property value.

Also change how we publish ILCompiler to better follow the model of crossgen2. This restores the expected behavior of publishing an AOT or single-file ilc.

Fixes failures in dotnet/sdk#45990

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[am11]

We need these files on linux-x64:

With this PR (and main), we have 201 files in tools/ including the whole sfx.

[jkoritzinsky]

@am11 where are you seeing those files being added? I'm checking the CI builds in this PR and it looks like I fixed that in 256edb9.

If this was checked locally, did you clean your build? The artifacts would have been left there from before the fix and caused issues.

[jkoritzinsky]

Yeah I've checked all of the binlogs and they're doing the right thing (no sfx in the tools dir). I'm going to merge this in.

[am11]

I was building it in GHA but it was using main branch https://github.com/am11/CrossRepoCITesting/releases/tag/linux_x64_12836857446. The PR branch did removed the extra files https://github.com/am11/CrossRepoCITesting/releases/tag/linux_x64_12837954845. Sorry for the confusion. Good fix! 👍