Description

I noticed that several internal helper functions in lib/utils.js were missing documentation. I have added JSDoc comments to these functions to improve code maintainability and assist future contributors in understanding the utility logic.

Changes

• Added JSDoc documentation for various internal helper functions to clarify their purpose and usage.
• Defined parameter types and return values for previously undocumented utilities to follow project standards

Type of Change

• Documentation update
• Bug fix
• New feature

Checklist

• My code follows the style guidelines of this project.
• I have performed a self-review of my own code.
• My changes generate no new warnings (Commitlint passed).

Summary by cubic

Added missing JSDoc comments to internal utilities in lib/utils.js to improve readability, IDE hints, and type safety. No runtime behavior changes.

Description

• Documented: findKey, toObjectSet, toJSONObject, isAsyncFn, isThenable, _setImmediate, asap.
• Clarified params/returns and edge cases (Buffer handling in findKey, circular refs in toJSONObject, thenable shape, setImmediate fallbacks).

Testing

• No tests added or changed; docs-only change.
• Tests not needed since there are no logic changes.

^{Written for commit cb5ed3c. Summary will update on new commits.}