D112 - GPU device selection prefers real silicon, and the device type is recorded as gradable provenance

Status: derived - the selection compiles and the gpudev record now carries the type.

The Vulkan backend used to take the first enumerated device. A Steam Deck with the Mesa software driver also present enumerates both its APU and llvmpipe, and first-is-fine would sometimes pick llvmpipe - reporting CPU results for a run meant to measure gfx1033, the exact provenance failure the GPU work exists to prevent. Selection now takes the first non-CPU device and falls back to llvmpipe only when that is all there is (the build VM).

gpudev gains a third field, the device type: integrated, discrete, cpu, virtual or other. That makes provenance machine-gradable - a consumer rejects a cpu result for a hardware claim without recognising device-name strings. On llvmpipe it reads gpudev|vulkan|llvmpipe (...)|cpu; the Deck's APU will read integrated. New field appended, so the contract holds.

The deck target itself (host-shaped, GPU=1, served via --serve) already existed; this is what makes it reach the right device. The RDNA2 run still awaits the hardware - proven on llvmpipe, a device swap away from silicon.