Document air.toml configuration within the cli help

Appreciate it is early days but would it be worth expanding the cli help to mention air.toml and the configuration options/defaults? This becomes more relevant if/when https://github.com/posit-dev/air/issues/111 is implemented. Currently we have

$ air --version; air format --help
air 0.2.0
Format a set of files or directories

Usage: air format [OPTIONS] [PATHS]...

Arguments:
  [PATHS]...  The files or directories to format

Options:
      --check  If enabled, format results are not written back to the file. Instead, exit with a non-zero status code if any files would have been modified, and zero otherwise
  -h, --help   Print help

Global options:
      --log-level <LOG_LEVEL>  The log level. One of: `error`, `warn`, `info`, `debug`, or `trace`. Defaults to `warn`
      --no-color               Disable colored output. To turn colored output off, either set this option or set the environment variable `NO_COLOR` to any non-zero value

Start with the air --version and air format --help entry points and locate where their CLI help text is defined. Review the air.toml configuration options and defaults, then update the help output to document them and verify the resulting command text.