List publishable keys

curl --request GET \
  --url https://app.usechar.ai/api/publishable-keys \
  --header 'Authorization: Bearer <token>'

{
  "keys": [
    {
      "id": "<string>",
      "name": "<string>",
      "key_prefix": "<string>",
      "revoked_at": "2023-11-07T05:31:56Z",
      "last_used_at": "2023-11-07T05:31:56Z",
      "created_at": "2023-11-07T05:31:56Z",
      "can_reveal": true,
      "allowed_origins": "<unknown>"
    }
  ]
}