add dc_has_unnoticed_chats() and dc_marknoticed_all_chats()

[Simon-Laux]

to fix this "bug" in desktop: deltachat/deltachat-desktop#3979

if these information are not easily available in the UI, we should consider adding dedicated core functions as dc_has_unnoticed_chats() and dc_marknoticed_all_chats() (due to multiple meanings, we avoid the the term "read" in the api, cmp)

~ deltachat/deltachat-desktop#3979 (comment)

mainly important to have them in the jsonrpc api because thats what desktop uses

[Septias]

Actually it should be enough to use getFreshMsgCnt in this line https://github.com/deltachat/deltachat-desktop/blob/f9b5e1290832bd45c82d9df70ee91f38884b93df/src/renderer/components/AccountListSidebar/AccountItem.tsx#L45
as getFreshMsgs filters out muted chats and getFreshMsgCnt does not. It also produces less traffic which is good.
No new API needed IMO, feel free to reopen if you disagree.

[r10s]

getFreshMsgCnt() is per-chat - not sure if that is the best way to help showing/hiding a menu entry in desktop's account sidebar, maybe i've overseen a simple things :)

but agree with closing the issue for now (even though i proposed the APIs that time :) it would be pretty special APIs for few benefits. let's discuss this in the original issue, i added an alternative idea there