[SMS App] Add highlighting to ConversationList view
Summary: Let the ListView use its default highlighting (did I not notice before?) and keep the currently-selected chat highlighted at all times
Test Plan:
- Launch app
- Use mouse or arrow keys to select a conversation. The highlight should follow the selected conversation
Reviewers: KDE Connect, apol
Reviewed By: KDE Connect, apol
Subscribers: apol, kdeconnect
Tags: KDE Connect
Differential Revision: https://phabricator.kde.org/D17612