[enh] Proposal to add class StringObject

I propose to add class StringObject. Then it will be possible to manipulate strings in object-oriented style:

$baseWord = new StringObject('soft', 'UTF-8');

$projectName = $baseWord
   ->preprend('yii')
   ->addWord('project')
   ->upperCaseEveryWord();

$projectNameWordsCount = $projectName->wordsCount();

Then we can make class StringHelper a wrapper over class StringObject. For example:

class StringHelper
{
    public static function createObject(string $string, string $encoding = null): StringObject
    {
        return new StringObject($string, $encoding);
    }

    public static function wordsCount(string $string, string $encoding = null): int
    {
        return static::createObject($string, $encoding)->wordsCount();
    }
}

No files or tests are named. Start by reading the existing StringHelper API and the issue discussion, then establish which StringObject methods and encoding behavior are in scope. Done requires an agreed API for the demonstrated operations and a consistent relationship between StringObject and StringHelper.