b10425

sycl: fuse the gated-delta-net state writeback cpy (#26643)

Port of #23940.

Arc Pro B70, Qwen 3.6 27B Q4_K - Medium (48 of its 64 blocks run
gated_delta_net), -ngl 99 -fa 1 -ctk f16 -ctv f16 -b 2048 -ub 2048,
interleaved A/B passes of r=3:

tg128 23.91 / 23.90 / 23.90 -> 24.19 / 24.17 / 24.20 +1.2%
tg128 (rebuild) 23.81 / 23.81 -> 24.09 / 24.10 +1.2%
pp2048 1050.8 / 1053.9 -> 1053.8 / 1054.5 flat
2 seqs, tg128 32.73 / 32.75 -> 33.11 / 33.10 +1.1%

Website:

• https://llama.app

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 7.14)DISABLED
• Ubuntu x64 (OpenVINO)
• Ubuntu x64 (SYCL FP32)
• Ubuntu x64 (SYCL FP16)

Android:

• Android arm64 (CPU)

Windows:

• Windows x64 (CPU)
• Windows arm64 (CPU)
• Windows arm64 (OpenCL Adreno)
• Windows x64 (CUDA 12) - CUDA 12.4 DLLs
• Windows x64 (CUDA 13) - CUDA 13.3 DLLs
• Windows arm64 (CUDA 13) (preview) - CUDA 13.4 DLLs
• Windows x64 (Vulkan)
• Windows x64 (OpenVINO)
• Windows x64 (SYCL)
• Windows x64 (ROCm 7.14)

openEuler:

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

• UI