"unread messages" filter

[nehemiagurl]

Checklist

• [X] I made sure that there are no existing issues - open or closed - to which I could contribute my information.
• [X] I made sure that there are no existing discussions - open or closed - to which I could contribute my information.
• [X] I have read the FAQs inside the app (Menu -> About -> FAQs) and my problem isn't listed.
• [X] I have taken the time to fill in all the required details. I understand that the bug report will be dismissed otherwise.
• [X] This issue contains only one feature request.
• [X] I have read and understood the contribution guidelines.
• [X] I optionally donated to support the Fossify mission.

Feature description

Add a filter view showing unread messages only, either via the three-dot menu or via a pulldown like how Signal does it¹:

https://github.com/FossifyOrg/Messages/assets/109424320/e3bdb3a0-762f-41c6-83ba-76f8bc6976a4

or even better: both! ¹ Signal actually does both, which is the best IMO

Why do you want this feature?

filtering for unread messages is an important decluttering tool in any messanger. even if one only uses SMS to get texts from the bank and the insurance company (which is actually the case for me), such a filter is still very useful.

Additional information

since Signal is AGPL, its license is compatible with Fossify and code can be borrowed without worry. whether the code itself is compatible with how the messenger is written is another question though...

[Aga-C]

We don't have information which message has been read or not. We only have information whether the whole conversation has been read. So this filtering could only show conversations marked as not read, not exact messages.

[nehemiagurl]

I mean in reality there's not really a difference when it comes to the filter. a conversation would show up whether there's one unread message or 1000. so maybe a better name is "unread conversations", but the rest of the request is pretty much the same.

[inson1]

@nehemiagurl so maybe tite should be changed?