fix: resolve PID validation, stack trace handling, and queue overflow…

[Sana9058]

This PR addresses the issues reported in #109 related to the JavaScriptEvaluator.

Summary of Fixes:

1. Fixed incorrect PID validation
   Updated the PID validation logic to ensure valid processes are not rejected due to falsy values such as 0.

2. Improved stack trace handling
   Ensured that error stack traces are preserved instead of being swallowed, making debugging easier.

3. Prevented queue overflow race condition
   Added proper queue length validation to prevent exceeding maxQueueDepth during concurrent operations.

Motivation:

These fixes improve the reliability and debugging clarity of the JavaScriptEvaluator by ensuring correct process validation, better error reporting, and safer queue management.

Notes:

• No breaking changes introduced
• Existing behavior preserved while improving stability
• Implemented based on the issue description

Please let me know if any changes or restructuring are required.

[Copilot]

Pull request overview

This PR updates JavaScriptEvaluator to improve error reporting and process validation, aligning with issues raised in #109.

Changes:

• Preserve stack traces when evalDangerously() rejects, and log errors to stderr (console.error).
• Fix child process PID validation to avoid rejecting valid (falsy) PIDs.
• Include stack traces when rejecting from child process error events.

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[Sana9058]

@mttrbrts Addressed review feedback:

• Added stack support to EvalResponse
• Improved error handling using instanceof checks
• Fixed queue overflow handling with early return
• Ensured DCO compliance

All checks are now passing. Please let me know if further changes are needed.

[mttrbrts]

Thanks for this contribution! This appears to be a duplicate of #110 by @Swastik-Prakash1, which was opened earlier and addresses the same issue (#109).

@Sana9058 — would you mind helping review #110? Your input would be valuable since you've worked on the same fix.

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This comment was generated by AI on behalf of @mttrbrts.

[Sana9058]

@mttrbrts Thank you for the clarification! Sure, I’d be happy to help review #110. Since I worked on a similar fix, I’ll go through it carefully and share my observations.
Thanks for pointing me to it.

[Swastik-Prakash1]

@mttrbrts Thank you for the clarification! Sure, I’d be happy to help review #110. Since I worked on a similar fix, I’ll go through it carefully and share my observations. Thanks for pointing me to it.

Yeah let me know too.. If u find anything interesting that can be worked on...