Force blksize=128 for linear attention on ascend

[jinminxi104]

Force blksize=128 for linear attention on ascend

Motivation

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Modification

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[Copilot]

Pull request overview

This PR updates the PyTorch executor’s KV-cache block-size adjustment logic to special-case Ascend devices when running models that use linear attention (detected via non-empty states_shapes), forcing the KV cache block size to 128.

Changes:

• Add an Ascend + linear-attention guard in ExecutorBase._adjust_block_size() that warns and overrides cache_config.block_size (and kernel_block_size) to 128.

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[grimoire]

LGTM