fix(tools): reject invalid retry attempt limits

[aiirvizionz]

Summary

• Reject non-positive and non-integer retry() attempt limits
• Prevent retry(fn, 0) from silently returning undefined without running fn
• Add regression coverage for invalid limits and successful later retries

Why

retry() currently uses a for loop from 1 through maxAttempts. When maxAttempts is 0, negative, or fractional, the loop may not run as intended and can silently hide a misconfiguration instead of failing clearly.

Validation

• node --test test\tools.test.mjs