Addition of a mine counter

[Azv121]

Is your feature request related to a problem? Please describe.
Everyday I mine X number of sentences. Currently I would have to count the number of sentences I have mined in either the 'Mining History' panel or in Anki. It would be great if there was a visible counter on the screen and an option to set an alert message which indicates that I have mined the set amount for that particular day.

Describe the solution you'd like
A mine counter which can be toggled visible in the settings and the counter displayed on the screen. This counter would increase as I click the 'Export' button so I can always see the number of mined sentences for a particular day. After a particular time (4am is the default in Anki) it can be reset back to 0. Also a section in the settings where I can set the daily counter limit. Once I have hit that limit an alert message can be displayed so I know I have done my mining for that particular day.