fix: improve admin contact validation messages

- Update error message for missing admin contact to be more concise
- Standardize admin contact validation message for invalid ident type
- Remove redundant error message formatting

The changes make admin contact validation messages more consistent
throughout the application, using "Admin contact" terminology instead
of "Administrative contact" for better clarity and consistency.

app/models/epp/domain.rb

@@ -29,9 +29,8 @@ def validate_contacts
     active_admins = admin_domain_contacts.select { |x| !x.marked_for_destruction? }
     active_techs = tech_domain_contacts.select { |x| !x.marked_for_destruction? }
 
-    # Проверка количества админ контактов
     if require_admin_contacts? && active_admins.empty?
-      add_epp_error('2306', 'contact', nil, 'Admin contacts are required')
+      add_epp_error('2306', 'contact', nil, 'Admin contact is required')
       ok = false
     end
 

config/locales/en.yml

@@ -81,7 +81,7 @@ en:
 
         domain:
           <<: *epp_domain_ar_attributes
-          admin_contact_invalid_ident_type: "Administrative contact with identification type '%{ident_type}' is not allowed"
+          admin_contact_invalid_ident_type: "Admin contact can be private person only"
 
         nameserver:
           attributes: