* fix: improve i18n compatibility for WPML, Polylang, and non-latin character support
- Add Label::get_safe_enum_name() utility with optional transliteration
for non-latin tax class/attribute/taxonomy names (#637, #409)
- Add "Transliterate non-latin characters" admin setting
- Replace get_page_by_path() with WP_Query for product slug resolution
so WPML/Polylang can hook into the standard query pipeline (#403, #368)
- Split product connections: `products` (toType: Product) and
`productsWithVariations` (toType: ProductUnion) so i18n plugins can
register language where args on the standard type name (#811, #952)
- Add ProductTypesWithVariationsEnum for the ProductUnion connection
- Add i18n compatibility tests
* chore: Linter compliances met