Latest message on a channel, formatted for preview.

e.g.

```
{
 created_at: '' ,
 messageObject: { ... },
 previews: {
   bold: true,
   text: 'This is the message preview text'
 },
 status: 0 | 1 | 2 // read states of latest message.
}
```


| Type |
| - |
| object |