Optimize Base58 encoding/decoding

[VolodymyrBg]

• Use Object.fromEntries for inverse alphabet creation
• Replace let with const for immutable variables
• Add bounds checking to prevent potential errors
• Optimize toBase58 and fromBase58 algorithms
• Improve type safety with explicit type annotations
• Special case handling for empty inputs

[45930]

I'm not convinced that there's enough value here to merge. Do you think this change actually improves o1js?

[mitschabaude]

this makes the code harder to read, and I don't see any significant improvements. wouldn't merge.

at least if you claim optimizations there should be benchmarks!