Mirrors the rocm/cuda pattern: ort::ep::OpenVINO with device_type "GPU"
(covers both Intel integrated graphics and Arc discrete GPUs through the
same EP), load-dynamic/dlopen so no OpenVINO toolkit is needed at build
time, and its own --openvino flag / backend = "openvino" config value.
Folded into the `full` feature alongside npu/rocm/cuda.
OpenVINO's provider options go through a generic key/value FFI interface
rather than a fixed C struct (unlike MIGraphX's OrtMIGraphXProviderOptions),
so it should be less exposed to the ABI-version-skew crash MIGraphX hit --
but that's inference from the EP's design, not verified against real
hardware. Like CUDA, this is compile-checked only: no Intel GPU in this
dev environment to runtime-verify against.
Version bump: breadmill 0.2.2 -> 0.2.3.
ROCm silently fell back to CPU: the code targeted ONNX Runtime's classic
ROCMExecutionProvider, but distro ROCm-enabled ONNX Runtime builds (e.g.
Arch's onnxruntime-rocm) are commonly compiled with --use_migraphx instead,
and registration failures were invisible since breadmill never installed a
tracing subscriber. Switches the rocm feature to target MIGraphX, adds a
default tracing subscriber so EP registration success/failure is always
visible, and fixes a real crash where MIGraphX's output sequence padding
could index the attention mask out of bounds during mean-pooling.
Also adds a CUDA backend (--cuda / backend = "cuda") mirroring the same
ort execution-provider pattern, for NVIDIA hardware.
Version bump: 0.1.0 -> 0.2.0.
