Extend WooCommerce translation boundaries

Public filters include:

• pom_translate_woocommerce_order_meta_allowlist( array $keys );
• pom_translate_woocommerce_order_meta_denylist( array $keys );
• pom_translate_woocommerce_email_exclusions( array $exclusions, $email, string $field );
• pom_translate_woocommerce_email_override( $override, string $email_id, string $field, string $locale ).

The email override defaults to null; return a string only when intentionally replacing the managed translation for that exact email field and locale.

Never allowlist payment tokens, private order notes, personal data, IDs, amounts, or operational metadata. Preserve WooCommerce's order-locale context and escape custom output for the email or account template.

Test customer and administrator emails, queued follow-ups, refunds, and two consecutive orders in different locales.