Refactor the shipment direction logic from 'outbound/inbound' to 'export/import' to align with the new database schema requirements. This includes updating the `ShippingRatesImport` logic, adjusting the Excel import sheet mappings, and removing the AED to IRR conversion during import as rates are now stored in AED.
Additionally, updated the shipment view action to open PDF documents in a new tab and updated the Phase 0 checklist with the new database schema requirements.
- docs: update Phase 0 checklist with new schema requirements
- refactor(ui): update shipment view actions to open in new tab
- refactor(import): update shipping rates import to use new direction enums and AED values
- docs: add file map and new excel document
