Retrieve a list of payment schedules with optional filtering.

This endpoint provides comprehensive search capabilities for payment schedules including:

• Status Filtering: Filter by payment schedule status (PENDING_APPROVAL, APPROVED, PENDING, etc.)
• Business Unit Filtering: Search schedules for specific business units
• Booking Filtering: Search schedules for specific bookings or booking references
• Date Range Filtering: Filter schedules by execution date ranges
• Sorting: Sort results by creation date, update date, or execution date