llama.cpp b9975 release rejects empty metadata keys

The llama.cpp project has published build b9975, which includes a change to reject empty metadata keys in GGUF files.

• macOS and iOS builds are available for Apple Silicon (arm64) and Intel (x64), along with an iOS XCFramework; KleidiAI support on macOS/iOS is disabled.
• Linux binaries cover Ubuntu x64, arm64, and s390x architectures across CPU, Vulkan, ROCm 7.2, OpenVINO, and SYCL backends.
• Android arm64 (CPU) builds are provided for mobile devices.
• Windows releases include CPU, OpenCL Adreno, CUDA 12/13, Vulkan, OpenVINO, SYCL, and HIP variants.
• openEuler support is partially disabled, with builds available for x86 and aarch64 architectures using ACL Graph.

This release provides updated binaries for various platforms and hardware accelerators while enforcing stricter validation on GGUF metadata.