Critical fix for product management location selection:
- Country/city callback_data now uses pipe | as separator with
encodeURIComponent/decodeURIComponent for special chars
- District selection uses location ID (prod_loc_{id}, shop_loc_{id})
instead of underscore-delimited country_city_district text
- Empty district names now show city name as fallback
- LocationService.getLocationsByCountryAndCity() returns id+district
for building callback_data with location IDs
- All error handlers in admin product navigation use editOrSendCallback
to avoid chat clutter
- Routes updated: prod_district_ → prod_loc_, shop_district_ → shop_loc_
This fixes the bug where selecting country/city/district in admin panel
or shop failed because split('_') broke on multi-word names or empty
district values.
5a9155613e