perf: replace internal object records with maps

[OrbisK]

🔗 Linked issue

❓ Type of change

• 📖 Documentation (updates to the documentation or readme)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

I was actually looking for other things and came across these improvements. In some places, you could certainly use a map instead of an object record, but that would then affect some exported APIs.

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

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commit: a3fc107

[farnabaz]

Thanks for the PR,
Although that PR looks good, but I'm not sure about the performance improvement here, Map has overhead of indexing had is good choice for large set of data, but here we are using object for small set of data which is slightly faster in object as far as I know.

It would be great if we can have a benchmark two decide between them.

[farnabaz]

I ran a small test on Map and Object and the result was almost same with small data.
Beside performance using map is better for security and readability.

Thanks for PR