isValidPackageName static method
Checks if a string is a valid Dart package name. Must be lowercase, alphanumeric + underscores, start with letter, not a Dart reserved word.
Implementation
static bool isValidPackageName(String input) {
if (input.isEmpty) return false;
if (!RegExp(r'^[a-z][a-z0-9_]*$').hasMatch(input)) return false;
return !_reservedWords.contains(input);
}