[BugFix] Set enable_cache_output as false by default

[rainyfly]

Motivation

测试发现开启缓存输出时，会偶现报错，暂时默认关闭缓存输出功能。

Modifications

设置缓存输出功能的默认值为 False

Usage or Command

None

Accuracy Tests

None

Checklist

• Add at least a tag in the PR title.
  • Tag list: [[FDConfig],[APIServer],[Engine], [Scheduler], [PD Disaggregation], [Executor], [Graph Optimization], [Speculative Decoding], [RL], [Models], [Quantization], [Loader], [OP], [KVCache], [DataProcessor], [BugFix], [Docs], [CI], [Optimization], [Feature], [Benchmark], [Others], [XPU], [HPU], [GCU], [DCU], [Iluvatar], [Metax]]
  • You can add new tags based on the PR content, but the semantics must be clear.
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• Add unit tests. Please write the reason in this PR if no unit tests.
• Provide accuracy results.
• If the current PR is submitting to the release branch, make sure the PR has been submitted to the develop branch, then cherry-pick it to the release branch with the [Cherry-Pick] PR tag.

[paddle-bot]

Thanks for your contribution!

[Copilot]

Pull request overview

这个PR修复了一个与缓存输出相关的bug,将 enable_output_caching 的默认值从 True 改为 False,以避免偶现的错误。

• 修改 EngineArgs 类中 enable_output_caching 字段的默认值
• 使 args_utils.py 中的默认值与 config.py 保持一致
• 不影响显式启用该功能的测试用例

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
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Additional details and impacted files

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