proof's macOS power path shelled out to the external `macmon` binary, so
the real-hardware energy bracket only worked when macmon was installed.
Replace it with a direct IOReport Energy-Model read (the validated
apple_ioreport FFI), mirroring the Linux RAPL path: two samples bracketing
a sleep, energy delta / window = watts. No sudo, no external binary —
proof's real-energy measurement now works out-of-box on Apple Silicon.
Also made the doc honest: Apple's Energy Model is a vendor model, so a
macOS reading is ModelBased-grade, not a true coulomb-shunt HwShunt (Linux
RAPL is the shunt-grade path). Removed the now-dead `mean` helper.
10 proof-cascade tests green (incl. power_is_plausible_when_available
reading real IOReport watts, and the end-to-end marginal measurement),
clippy clean.
Co-Authored-By: Claude Opus 4.8 <[email protected]>
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