Completion box improvements

[marad]

Using completion box feels weird.

• Enter adds new line, but doesn't close the suggestions
• up/down keys skip 2 suggestions at once
• it would be better if going up/down on the edge of the list would wrap to end/begginning of it

[marad]

Fixed in https://github.com/marad/note-grove/commit/551cd9a9dd3fc8d4ac7d9d7e98a24059a552f52a