Replace `f64` with `Decimal` in `DeltaInfo` Struct

[joaquinbejar]

Description

Refactor the DeltaInfo struct to replace all instances of the f64 type with the Decimal type. This change aims to improve numerical precision and reduce the risk of floating-point inaccuracies, especially in financial calculations where precision is critical. Ensure that all associated methods, logic, and tests are updated to accommodate this change.

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Tasks

Implementation:

• Replace the f64 fields in the DeltaInfo struct with Decimal:
  • net_delta: Decimal
  • individual_deltas: Vec<Decimal>
  • neutrality_threshold: Decimal
• Update any methods or logic that rely on these fields to use the Decimal type.
• Ensure compatibility with the Positive type for underlying_price.

Testing:

• Update existing unit tests to use Decimal values instead of f64.
• Add new tests to validate the behaviour with precise decimal inputs, including edge cases:
  • Very small and very large values.
  • Decimal rounding scenarios.

Documentation:

• Update documentation for the DeltaInfo struct to reflect the change to Decimal.
• Add comments to explain the choice of Decimal for enhanced precision.

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Additional Notes

• Consider using the rust_decimal crate for the Decimal implementation.
• Ensure that any external interfaces or serialization/deserialization mechanisms (e.g., JSON) are compatible with the Decimal type.
• Verify performance implications of using Decimal in calculations and provide benchmarks if necessary.

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Labels

refactor, precision, enhancement, testing, documentation