Make Iranian Rial (IRR) the sole base currency for shipping rates:
- RateImportService now converts all imported rates to IRR at import
time using the current daily exchange rate (source currency AED/USD/
EUR/IRR). Rates are stored in rate_entries with currency='IRR'.
- PriceCalculatorService looks up IRR rates directly — no conversion
at calc time. Also fixes a pre-existing bug where extras (in IRR)
were incorrectly added to the AED base before conversion.
- RateEntry::lookup() default currency changed from 'AED' to 'IRR'.
- Migration changes the column default to 'IRR'.
- Filament import form: relabel 'Rate currency' to 'Source currency
(in Excel file)' with helper text explaining the conversion.
- WordPress JS: update price summary labels from 'درهم' to 'ریال'
and drop the deprecated net_dirham field.
Architectural benefit: rates are 'frozen' in IRR at import time —
daily exchange rate changes only affect NEW imports, not already-
stored rates. This is more stable and predictable for customers.
Implement a new pricing architecture based on a 4-quadrant model (Export/Import
x Document/Non-Document) to replace the previous 2-zone model. This includes
the ability to handle different zones for parcels and documents per country.
- Add `RateEntry` and `CountryZone` models for managing complex rate matrices.
- Implement `RateImportService` to parse Excel templates using PhpSpreadsheet.
- Add `RateImportResource` in Filament for administrative rate uploads.
- Refactor `PriceCalculatorService` to utilize the new 4-quadrant lookup logic.
- Add database migrations to extend `rate_entries` and create `country_zones`.
- Update `DEPLOYMENT.md` with new architectural details and deployment steps.
