Exported with the conv1d-as-conv2d lowering, the slice-based STFT magnitude,
hoisted cross-attention K/V and a head-major KV layout. Requires the ExecuTorch
1.4.1 Vulkan runtime from the v0.10.0-libs-1.4.1 artifacts (gelu clamp, reduce
barrier and Adreno local-work-group fixes).