[Feature] Multi-selection support for tasks

### Is there an existing issue for this?

- [X] I have searched the existing issues

### Feature type

User interface/User experience

### Problem

It is hard to perform bulk actions on multiple task items, such as bulk removal or bulk mark as done/archived.

### Description

There should be the ability to allow for multi-selection of items by holding on an item to start multi-select mode, similar to the contextual action bar pattern in the views world. A CAB should then be shown with actions to:

* Mark as completed
* Mark as archived
* Delete tasks

And an option to "Select all" items.

Perhaps we could also add the option to push the selected items' due dates forward by days.

### Alternatives?

_No response_

### Additional info

There _was_ a previous implementation of the CAB that worked with the recyclerview-selection artifact, but it broke due to an action bar not being present before the CAB would be shown, so when holding on an item to enter the selection mode it would crash with a runtime exception.