Expose information about the current range to the datepicker actions

#### What are you trying to do?

I am trying to disable the apply button inside mat-date-range-picker-actions until a range is selected

#### What troubleshooting steps have you tried?

tried to see if any events fire on day selection so I can determine if the range is correct

#### Reproduction

https://stackblitz.com/edit/angular-date-range-picker-actions?file=src/app/date-range-picker-forms-example.html
Well, here is a start point. I could not find a way to disable the Apply button until both dates are selected.
Reson is the form data is not updated until Apply is clicked and I could not find any events that trigger on day selection. There are some for year and month but not day.

#### Environment

- Angular: 12
- CDK/Material: latest
- Browser(s): N/A
- Operating System (e.g. Windows, macOS, Ubuntu): N/A

Comienza con la reproducción vinculada de StackBlitz y sigue cómo mat-date-range-picker-actions recibe el estado y cómo se expone la selección de días. Se considera terminado cuando las actions puedan determinar si ambas fechas del rango actual están seleccionadas, lo que permite que el botón Apply permanezca deshabilitado hasta que el rango esté completo.

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