chore: bump llama.cpp to b9724

[github-actions]

llama.cpp update

• Previous pin: b9699
• New pin: b9724
• Upstream release: https://github.com/ggml-org/llama.cpp/releases/tag/b9724
• Compare: ggml-org/llama.cpp@b9699...b9724

Upstream changelog

Release notes for b9724

Details

mtmd: several bug fixes (#24784)

• mtmd: several bug fixes

• fix build

• fix gemma4ua

• add sanity check in get_u32()

• fix build (2)

• area() avoid overflow

macOS/iOS:

• macOS Apple Silicon (arm64)
• macOS Apple Silicon (arm64, KleidiAI enabled) DISABLED
• macOS Intel (x64)
• iOS XCFramework

Linux:

• Ubuntu x64 (CPU)
• Ubuntu arm64 (CPU)
• Ubuntu s390x (CPU)
• Ubuntu x64 (Vulkan)
• Ubuntu arm64 (Vulkan)
• Ubuntu x64 (ROCm 7.2)
• Ubuntu x64 (OpenVINO)
• Ubuntu x64 (SYCL FP32)
• Ubuntu x64 (SYCL FP16)

Android:

• Android arm64 (CPU)

Windows:

• Windows x64 (CPU)
• Windows arm64 (CPU)
• Windows x64 (CUDA 12) - CUDA 12.4 DLLs
• Windows x64 (CUDA 13) - CUDA 13.3 DLLs
• Windows x64 (Vulkan)
• Windows x64 (OpenVINO)
• Windows x64 (SYCL)
• Windows x64 (HIP)

openEuler:

• DISABLED
• openEuler x86 (310p)
• openEuler x86 (910b, ACL Graph)
• openEuler aarch64 (310p)
• openEuler aarch64 (910b, ACL Graph)

UI:

• UI

Commit range

Commits from b9699 to b9724 (first 80)

• [SYCL] rename GGML_SYCL_SUPPORT_LEVEL_ZERO (#24719) (9724f66)
• mtmd: refactor preprocessor, add mtmd_image_preproc_out (#24736) (24bba7b)
• server: fix router args not being forwarded to child instances (#24760) (968c438)
• server: (router) rework -hf preset repo (#24739) (552258c)
• server : return HTTP 400 on invalid grammar (#24144) (#24154) (1078621)
• ui: provide touch accessible model selection UI (#24604) (2083217)
• server : add last-5-seconds generation speed display (#24291) (0802307)
• server: add "schema" and validation (#24150) (e1efd09)
• server: (router) fix stopping_thread potentially hang (#24728) (fe7c8b2)
• docs: fix export-lora --lora-scaled syntax [no release] (#24703) (7b6c5a2)
• hexagon: support for op-trace (fine-grain tracing of HVX/HMX/DMA events) (#24592) (d2c6795)
• mtmd: refactor llava-uhd overview image handling (always use ov_img_first) (#24769) (060ce1b)
• cmake : fix ui build with read-only source (#24752) (32eddaf)
• mtmd: add batching for mtmd-cli, add video tests (#24778) (a6b3260)
• server: add "X-Accel-Buffering": "no" header to streaming endpoints (#24774) (40f3aaf)
• Ggml/cuda col2im 1d (#24417) (3a3edc9)
• mtmd: add batching support for internvl (#24775) (db52540)
• ggml-cpu: support K tails in power10 Q8/Q4 MMA matmul (#24753) (8141e73)
• server : consolidate slot selection into get_available_slot (#24755) (80452d6)
• pi : remove docs from system prompt (#24791) (5bd21b8)
• ggml : bump version to 0.15.2 (ggml/1548) (1868af1)
• sync : ggml (5fd2dc2)
• server: fix non-bound n_discard value (ctx shifting) (#24786) (159d093)
• spec: support eagle3 for qwen3.5 & 3.6 (#24593) (b14e3fb)
• mtmd: several bug fixes (#24784) (e2e7a9b)

Web bridge review focus

Please pay extra attention to upstream changes touching:

• WebGPU, WASM, Emscripten, pthreads, or memory64 build behavior
• ggml backend APIs used by the bridge
• model loading, tokenizer, chat template, context/state persistence, or cache semantics
• CMake/build flags that can affect the generated JS/WASM artifacts

Validation

• Emscripten build passed
• Browser WebGPU/state-persistence smoke passed
• Generated bridge artifacts include wasm32 and memory64 outputs
• No stale hard-coded llama.cpp tag remains in CI/publish defaults

Automation behavior

This PR is managed from the stable branch automation/bump-llama-cpp. If another llama.cpp release appears before merge, the scheduled workflow updates this same PR instead of opening a duplicate. The workflow skips if a non-automation PR already changes llama_cpp.version.