Add three-dot menu to thread narrow

[WesleyAC]

The "stream info" button in the thread narrow screen should be replaced with a three-dot overflow menu, which has the same options as the actionsheet that is opened on long-press. We should be able to share the code for that pretty easily.

See prior discussion in #4532 and on CZO.

[Gautam-Arora24]

Working on this!