Add benchmarks for Quantity operations

[theycallmeaabie]

Summary

• Add benchmarks for BigQuantity and UInt64Quantity operations (Add, Sub, Cmp)
• Add benchmark for ToQuantity parsing

Resolves #1467

[Copilot]

Pull request overview

Adds Go benchmarks to track performance of Quantity implementations and parsing over time (per #1467).

Changes:

• Adds benchmarks for BigQuantity operations: Add, Sub, Cmp
• Adds benchmarks for UInt64Quantity operations: Add, Sub, Cmp
• Adds a benchmark for ToQuantity parsing

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[adecaro]

Hi @theycallmeaabie , please, resolve the conflicts 🙏

[theycallmeaabie]

Done!