Improved Hire Purchase & Finance System

This script expands and refines the hire purchase system with a much more complete and realistic finance experience. It adds multiple finance plan options with different deposit amounts, APR rates, and balloon payment choices, and provides a clear display of payment terms in years and months.

Key improvements include:

• Detailed finance management screen showing plan type, current agreement status, monthly payment, APR, payment progress, final/balloon payment, remaining balance, and early settlement cost
• Delinquency tracking with increasing late-payment surcharges through multiple stages before repossession
• Repossession grace period giving the player one final opportunity to settle the agreement
• Automatic sale of repossessed vehicles if the agreement is not cured during the grace period
• Manual early payment support including balloon payments
• Enhanced early settlement confirmation showing remaining balance, settlement amount, current farm balance, and projected balance after settlement
• Combined monthly finance summary with payments, late agreements, repossessions, and completed agreements
• Improved save/load handling for delinquency and repossession states
• Full GIANTS Test Runner validation completed with all checks passing