Refactor distance calculation to use Haversine formula

[babiaraujo]

• Replace the previous distance calculation method with the Haversine formula to improve accuracy over long distances.
• Introduce a degreesToRadians utility function to enhance code readability and reduce redundancy.
• Add detailed comments to the getDistanceBetweenCoordinates function and degreesToRadians utility function to improve documentation and understandability of the calculation logic.
• Define earthRadiusKm as a constant to clarify the use of Earth's radius in the distance calculation and facilitate potential adjustments.

This update ensures more precise distance measurements between geographical coordinates and improves the maintainability and clarity of the code.