Robust configuration management experience

> I’m not using a screen reader but I would suggest that when you first time start the “copilot” it provides an interactive dialog to prepare the configuration for the user in its home directory.
> - Then we can add a cli option to skip this initial setup behavior.
> - Add a cli option to define an alternative location for a config file.
> - Add a sub-command “config” which allows us to “show”, “option”, “get”, “set”, “locate”, “init” the configuration file. The options like “show”, … “init” should be sub-commands of “config”. The sub-command “option” should show for a given name (property) of an option the description out with the possible values and type (str, number, array, object) and with examples.
> - all cli options should be configureable via the configuration file, and when the cli commandline defines the same option from the configuration again then the cli option wins and takes advantage before the value from the configuration file.
>
> it might be also possible to detect screen reader devices and automatically suggest to configure it when we start “copilot” the first time or when we connect a screen reader device after we done the setup already and didn’t set a option like “detect_screen_readers” to “false”.
>
> I miss that we can configure the cli via the config and that I have to add always the cli options and have to create aliases etc.

_Originally posted by @tobiashochguertel in [#199](https://github.com/github/copilot-cli/issues/199#issuecomment-3368238832)_