chatgui: double-click member edit, fix delegate backgrounds; transport: invite_sync/member_sync robustness

tools/chatgui/src/channeldelegate.cpp

@@ -28,6 +28,8 @@ void ChannelDelegate::paint(QPainter *painter, const QStyleOptionViewItem &optio
         painter->fillRect(option.rect, option.palette.highlight());
     } else if (option.state & QStyle::State_MouseOver) {
         painter->fillRect(option.rect, option.palette.light());
+    } else {
+        painter->fillRect(option.rect, option.palette.base());
     }
 
     /* ── vertical status bar (left edge, over background) ── */