Message deep links

Add a link button to messages (both user and assistant) to create a deep link to the message.

By going to this link corresponding chat should be opened and being scrolled to the message.

Use case:
During working in chat I decide that I can go back to the same message later to read it again. Using link I can save it in my to-do list and go back to it any time without having to save the whole message in external source.