[XPU] fix thinking bug where output only contains reasoning_content

[ddchenhao66]

Motivation

1. 在模型效果导致输出只有思考没有正常回复内容的场景，推理引擎兜底处理，强制将eos token改为think end token；
2. limit_thinking_content_length_v1/2算子增加CPU实现。

Modifications

Usage or Command

Accuracy Tests

Checklist

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