B.Melnik 85ee81cfa3 feat(StatusChatList): Add drag and drop support of list items
This implements drag and drop capabilities of chat items within a `StatusChatList`.
The commit introduces a `DelegateModal` to visually reorder chat items
when they're being dragged and dropped onto a `DropArea`.

To persist the new order of chat items, various signals have been introduced to chat
list related components:

```qml
StatusChatList {

    onChatItemReordered: function (id, from, to) {
        // ...
    }
}

StatusChatListAndCategories {

    onChatItemReordered: function (categoryId, chatId, from, to) {
        // ...
    }
}
```

There's no such API on the `StatusChatListCategory` type because that one already
exposes its underlying `StatusChatList` via `chatList`, which makes the signal available.

Dragging and dropping chat items is disabled by default and needs to be turned on
using the `draggableItems` property:

```qml
StatusChatList {
    draggableItems: true
    ...
}
```
2022-09-21 18:20:03 +02:00
..