Add OpenVINO GenAI C runtime for Voxtype NPU support

[jacob-vincent-mink]

Summary

• add Spencer Bull’s source-built openvino-genai package
• update it to OpenVINO GenAI 2026.3.1.0 and require Arch openvino=2026.3.1
• ship libopenvino_genai_c.so, which Voxtype 1.1’s runtime-loaded OpenVINO backend requires
• use Arch’s official openvino-intel-npu-plugin; it pulls the current intel-npu-driver and compiler
• advertise the GenAI runtime and NPU plugin from voxtype-bin
• backport upstream OpenVINO GenAI 398fbc14 to fix an unresolved format<int> symbol and add a package-time C ABI load check

Validation

• official package build completed and contained the expected GenAI, tokenizer, and GenAI C shared libraries
• ldd -r and ctypes.CDLL("libopenvino_genai_c.so") exposed the upstream linkage bug; both pass with the backport
• Voxtype 1.1.0-rc4 downloaded a fresh OpenVINO model, compiled its NPU cache, and transcribed a WAV on a real Intel NPU with device=NPU and no fallback
• repository self-tests pass

Release sequencing

Keep draft until the fixed pkgrel=2 artifact is produced by the official builder and voxtype-bin 1.1.0 is released.

Co-authored package work from @spencerbull.

[spencerbull]

LGTM after we update the sha

[jacob-vincent-mink]

LGTM after we update the sha

done

[spencerbull]

still having group issues to access /dev/accel/accel0

[spencerbull]

@jacob-vincent-mink can you provide an update on what we're waiting on here