create nicegui app with basic command line to start

[WolfgangFahl]

nicescad -h
usage: nicescad [-h] [-a] [-c] [-d] [--host HOST] [--port PORT] [-s] [-V]

Copyright 2023 contributors. All rights reserved.

  Licensed under the Apache License 2.0
  http://www.apache.org/licenses/LICENSE-2.0

  Distributed on an "AS IS" basis without warranties
  or conditions of any kind, either express or implied.

options:
  -h, --help     show this help message and exit
  -a, --about    show about info [default: False]
  -c, --client   start client [default: False]
  -d, --debug    show debug info [default: False]
  --host HOST    the host to serve / listen from [default: localhost]
  --port PORT    the port to serve from [default: 9858]
  -s, --serve    start webserver [default: False]
  -V, --version  show program's version number and exit

[WolfgangFahl]