List Inboxes

{
  "data": [
    {
      "id": "inb_901",
      "name": "Support Email",
      "channel_type": "Channel::Email",
      "greeting_enabled": false,
      "created_at": "2026-08-01T10:00:00Z"
    },
    {
      "id": "inb_902",
      "name": "Website Live Chat",
      "channel_type": "Channel::WebWidget",
      "greeting_enabled": true,
      "greeting_message": "Hello! How can we help you today?",
      "created_at": "2026-08-02T11:00:00Z"
    }
  ]
}