chore: themes commands

[notnmeyer]

➜ task -- themes -h

  Manage themes

  USAGE


    loops themes [command] [--flags]


  COMMANDS

    get <id>        Get a theme
    list [--flags]  List themes

  FLAGS

    --debug         Print API request details before sending
    -h --help       Help for themes
    -o --output     Output format (text, json) (text)
    -t --team       Team key name to use