hide domain in mentions

[breadguyyy]

Summary

add a setting to hide instance domain of mentions in notes

Purpose

will look a little cleaner, especially in threads with multiple users.

Do you want to implement this feature yourself?

• [ ] Yes, I will implement this by myself and send a pull request

[breadguyyy]

changed my mind about this, i would prefer if mentions atthe beginning of messages were condensed to one line somehow, like a "..." that could be expanded or something. mentions add up quickly in threads and it would be nice to clean it up a bit