perf: optimize hot path iteration and destructuring

[shenald-dev]

Optimized iteration loops in /v1/chat/completions validation logic by replacing for...of loops with classic indexed for loops with cached length. Optimized request body property access by removing object destructuring with || {} fallbacks in favor of explicit validation, reducing garbage collection pressure and increasing overall throughput in benchmark scripts. All changes pass unit test cases and lifecycle documents and changelogs have been successfully synced and tagged to version v1.1.27.

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PR created automatically by Jules for task 10765501706318757268 started by @shenald-dev

[google-labs-jules]

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[shenald-dev]

Looks good; consider adding a brief comment explaining the performance rationale for the loop change.

Reviewed — quality: high

[shenald-dev]

Looks good, merging this in. CI is green and everything checks out 👍

Optimize hot path iteration and destructuring in validation logic for better performance

[google-labs-jules]

Looks good, merging this in. CI is green and everything checks out 👍

Optimize hot path iteration and destructuring in validation logic for better performance

Acknowledged.

[google-labs-jules]

Looks good; consider adding a brief comment explaining the performance rationale for the loop change.

Reviewed — quality: high

Added the requested inline comment explaining the performance rationale for the loop optimization.