Show the year of the message

**Is your feature request related to a problem? Please describe.**
The year of the message is never shown in the UI, even if the message is from last year.

**Describe the solution you'd like**
On other platforms (Android and web), the year is shown when the message is at least 1 week old. It would be nice to have the same behavior.

**Describe alternatives you've considered**
I tried to look at the message source, but the date seems to be from epoch, so not really human readable.

Start by locating the iOS message UI code that formats and displays message dates, then compare its behavior with the Android and web clients described in the issue. Implement the one-week threshold so older messages include the year, and verify that message dates display the expected year in the UI.

Written by the indexing model from the issue text.