- Introduced new routes for processing invoices in the router.
- Added `InvoiceStatus` enum to manage invoice states.
- Enhanced `InvoiceHeader` and `InvoiceFinancials` models with new fields for status tracking and total packages.
- Updated schemas to include new fields for invoice processing.
- Implemented API methods for processing invoices and checking process status in the frontend.
- Removed outdated validation files related to invoice processing.