This broke during the modal refactoring because we're no longer relying
on `chatsModel.contextChannel`.
Passing the channel item to the popup ensures it's properly hydrated again.
Closes#3050
This commit replaces the `TopBar` components with StatusQ's `StatusChatToolBar`
and touches a few other things as part of this refactoring, namely:
1. `ChannelContextMenu` has been renamed to `ChatContextMenu` and is now a `StatusPopupMenu`
2. Leftover components have been removed: `StatusChatInfo`, `StatusChatInfoButton` and `TopBar`
3 `ActivityCenter` has been moved into `ChatColumn.qml` because `StatusChatToolBar` doesn't provide it
4. `Share chat` option in `ChatContextMenu` has been removed as it wasn't doing anything.
Closes#2746