Feature: add a way to delete read notifications

[Dehelssey]

Currently there's no way to clear notifications list.

IMO we should add a button to clear the whole list at once.

A nice addition would be to also have a swipe action to clear notification one by one. (removed from this issue, opened in a new one: see #3138 )

Let me know if I should make two separate issues one for each option :)

[shuuji3]

Agreed, it would be nice to have a feature.

The "Clear all" feature is easier to implement. Probably, we could store the last seen post ID and filter the post. Or Mastodon API has an option for that.

Could you create a separate one for "clear notification one by one"? That will require a bit more efforts.

[Dehelssey]

Could you create a separate one for "clear notification one by one"? That will require a bit more efforts.

Will do!