#28151 WebGPU: Support Split-K with batch size > 1

Description

This patch adds the support of Split-K with batch size > 1 by
encoding both batch index and Split-K index in dispatch_z and
decompose them in the shader via:
batch = logical_global_id.z / num_k_splits
split_index = logical_global_id.z % num_k_splits

This patch also adds batch size to the criteria of using Split-K
as increasing batch size will also increasing the parallelism,
reducing the effectiveness of Split-K.

This patch also replaces consteval with constexpr in
ort_version_check.h to workaround a compilation error
about vs2022.

Motivation and Context

With this patch we can improve the performance of
sam-vit-b-decoder-static-fp16-demo (7.5%) on Intel PTL.