feat: can use escaped tokens inside quotes including quotes. Change tokenizer to support: cmd with arg "string with embedded \" double quote" works for single quotes too. Mixed quotes can skip the \" or \' escaping. Also: quoted cmds args "can include \n newline, \t tab and \r return" Added a doc example, also tests for new feature.

# https://issues.roundup-tracker.org/issue2551278
# datetime.utcnow deprecated
try:
    from datetime import UTC, datetime

    def utcnow():
        return datetime.now(UTC)

except ImportError:
    from datetime import datetime

    def utcnow():
        return datetime.utcnow()