Because we've switched to `QuotedMessage` as an attached payload to
messages to make message replies data more reliable, we lost some of
the author information in imported messages, that was available prior
to that move.
This commit introduces `quotedMessageAuthorDisplayName` and
`quotedMessageAuthorAvatar` to our model so it can be set in case
we can't retrieve contact details for a given message (which is always
the case for imported messages)
New messages marker had a clock value of "0" before. Since all
messages are inserted based on the clock value, new messages marker
would cause other "0"-valued clock items to be inserted after it,
effectively making chat header being displayed in the middle of the
chat.
Setting new messages marker clock value to the clock of the message it
points to solves the issue.
fixes: #8955
Pascal Precht
Patryk Osmaczko
Jonathan Rainville