Bugfix: Butex returned to ObjectPool triggers use-after-poison

[chenBright]

What problem does this PR solve?

Issue Number: #2890

Problem Summary:

What is changed and the side effects?

Changed:

Butex object returned to the ObjectPool may be accessed, so ObjectPool can not poison the memory region of Butex.

Side effects:

• Performance effects:

• Breaking backward compatibility:

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Check List:

• Please make sure your changes are compilable.
• When providing us with a new feature, it is best to add related tests.
• Please follow Contributor Covenant Code of Conduct.

[Copilot]

Pull Request Overview

This PR prevents ASan from poisoning memory for TaskNode and Butex objects returned to their respective object pools, avoiding use-after-poison errors.

• Adjusted comment style in execution_queue_inl.h for TaskNode::cancel().
• Added ASan-poison specialization for bthread::Butex in butex.cpp.
• Updated Chinese documentation with examples for disabling ASan poisoning on object pools.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
src/bthread/execution_queue_inl.h	Refined comment formatting for TaskNode::cancel().
src/bthread/butex.cpp	Added ObjectPoolWithASanPoison<bthread::Butex> specialization.
docs/cn/sanitizers.md	Included example for disabling ASan poisoning on Butex.

Comments suppressed due to low confidence (1)

src/bthread/butex.cpp:131

• Consider adding a unit or integration test to verify that the ASan poison specialization for Butex prevents poisoning as intended.

struct ObjectPoolWithASanPoison<bthread::Butex> : false_type {};

[wwbmmm]

LGTM