Allow to show the current progress in the window titlebar

When building a snap with several parts using -v, it's usually not possible to know which part is being built due to the long text output. An idea (with a much-to-be-desired proposal here: https://github.com/snapcore/snapcraft/pull/4217 ) would be to allow to show the progress text in the window titlebar, by using the ANSI codes for that.

A proposal would be to add a new boolean named parameter to the `progress` method, that, when set to True, will not only show the string in the screen, but also set it as the window title.

These are some ideas for that named parameter:

- update_titlebar
- set_titlebar
- set_on_titlebar
- titlebar
- on_titlebar
- copy_on_titlebar
- dup_on_titlebar