Add build-time check for QueryUnbiasedInterruptTime availability

[steveisok]

Several places in the runtime call QueryUnbiasedInterruptTime as a higher-fidelity replacement for GetTickCount64. This API is only available for desktop and UWP apps per the documentation — it is not available in all Windows partitions (e.g. the GAMES partition).

Affected callsites

File	Function
src/coreclr/gc/windows/gcenv.windows.cpp	GCToOSInterface::GetLowPrecisionTimeStamp
src/native/minipal/time.c	minipal_lowres_ticks
src/libraries/.../System/Environment.Windows.cs	Environment.TickCount64

Proposal

Add a CMake feature check (e.g. HAVE_QUERYUNBIASEDINTERRUPTTIME) that detects whether the API is available, and use it consistently across all callsites. For native code this would flow through minipalconfig.h; for managed code it could be an MSBuild property driving a conditional compilation symbol.

When the API is unavailable, GetTickCount64 is an appropriate fallback — it was the prior implementation at all three sites.

Note

This issue was drafted with the assistance of GitHub Copilot.

[steveisok]

/cc @lateralusX @jbevain

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[steveisok]

If this has a place in main, do we treat these as one-offs as they come up? Or do we want to capture all of these around a common check?

[tannergooding]

This may need additional consideration as GetTickCount64 is explicitly not high enough precision for certain domains, such as games, and the underlying OS wait APIs were all changed to use a different timer source in the Windows 7-8 timeframe.

What of the other common timer APIs are available in the GAMES partition and can we opt to use those instead if compiling for that target?