expose platform-specific PRIO_DARWIN_* constants for core type selection on macOS in os module. #103545
Description
Feature or enhancement
As described in this stack overflow answer, the way to select "efficiency" vs. "performance" cores on Apple Silicon macOS machines is to use setpriority. However, you need to use custom platform-specific constants to do this, specifically, PRIO_DARWIN_BG, and either PRIO_DARWIN_THREAD or PRIO_DARWIN_PROCESS.
Pitch
It's just a few integer constants and it would expose a pretty important bit of power-efficiency/performance-tuning functionality for Python.
Previous discussion
No previous discussion anywhere, this seems like a fairly minor addition. This platform-specific functionality seems consistent with the way these functions are already treated, given that os.PRIO_* are already "Unix, not Emscripten, not WASI".