_add_arguments() adds the global options to self.__parser instead of
to the parser it receives. The two are the same object, because the
only caller passes self.__parser, so the change is not observable.
Use the parser parameter instead, so that the method honors its
argument the way Cmd.add_arguments() does, and so that the global
options can be shared with other parsers, e.g. the subcommand
parsers, without rewriting this method.
Assisted-by: unsloth/Qwen3.8-27B-GGUF:Q4_K_M with pi.dev v0.84.2
Signed-off-by: Jan Lindemann <jan@janware.com>