[Feature Request] Add Import Tasks button to Settings.

When exporting my calendar and tasks from Google Apps it seems it is only possible to export one iCal file for the calendar and a separate iCal file for tasks.

Calendar features a 'Settings & Import' feature at the bottom left of the screen; however, Tasks just shows 'Settings', with no import feature.

Given this I thought there was no way to import tasks and opened https://github.com/nextcloud/server/issues/6877 in response.

I have now tried to upload the Tasks file via the Calendar app and it actually imported the tasks just fine. It was counter-intuitive to do this however. Another oddity of this is once imported the tasks display in Tasks, not Calendar.

Due to Google Apps popularity I believe it would be sensible to duplicate the Import button to Tasks to encourage seamless migration to Nextcloud.

You might also want to update "Settings" to "Settings & Import" to match Calendar.

Start by locating the Tasks Settings screen and comparing it with Calendar's “Settings & Import” entry point. Add an import button and update the label to match the requested wording, then verify that the existing task import flow remains accessible and imported tasks still appear in Tasks.