PITI Qualification Calculations

The primary purpose of this patch was to Introduced Max PITI-based qualification logic for loan scenarios, allowing qualification to be driven by a payment cap instead of DTI.

• Added support for setting a Max PITI amount on loan scenarios
• When enabled, Max PITI is used as the primary qualification constraint
• Qualification and pre-approval values are calculated based on the payment cap
• DTI is excluded as a qualifying factor for scenarios using Max PITI
• Improved flexibility for Loan Officers in structuring borrower qualification criteria