Vulkan raises mul_mat_id row-id limit to 1024 experts

The official source reports this update: b11029: vulkan: raise the hoisted row-id limit for mul_mat_id from 256 to 1024 experts. vulkan: raise the hoisted row-id limit for mul_mat_id from 256 to 1024 experts ( #28501 ) vulkan: raise the hoisted row-id limit for mul_mat_id to 512 experts The expert-count shader (count_experts.comp) sizes its shared arrays with BLOCK_SIZE, which is 256. Because of that, row-id hoisting is switched off for any model with more than 256 experts, and every mul_mat_id workgroup has to rescan the whole ids tensor on its own. Qwen3.8-Flash-Next has 512 experts and was quietly running on that slow path.