[FEATURE REQUEST] "Download all unread" from collection action

[liuandrew]

Preflight Checklist

• I have read and I agree to follow the support disclaimer.
• I am sure that my feature request has nothing to with third party extensions.
• I am using the latest available Paperback version (currently 0.8).
• I have searched the issue tracker for a feature request that matches the one I want to file, without success.

What type of Apple device is the feature request for?

All device types

Describe the feature

Add a button to download all unread chapters in a saved library collection.

Feature Motivation

If you have a lot of mangas stored in a collection, going through one by one and tapping "Download Unread Chapters" is tedious. Since downloading unread chapters is already an option, I imagine it shouldn't be too difficult to just reuse that action on all items in the collection?

Anything Else?

No response