findByPhoneCode static method
Find the first country by phone code.
Supports inputs with and without '+' prefix.
Implementation
static Country? findByPhoneCode(String phoneCode) {
final normalized = _normalizePhoneCode(phoneCode);
if (normalized.isEmpty) return null;
final countries = _countriesByPhoneCodeAll[normalized];
if (countries == null || countries.isEmpty) return null;
return countries.first;
}