Connects to an in-progress EVI chat session. The original chat must have been started with allow_connection=true. The connection can be used to send and receive the same messages as the original chat, with the exception that audio_input messages are not allowed.
Access token used for authenticating the client. If not provided, an api_key must be provided to authenticate.
The access token is generated using both an API key and a Secret key, which provides an additional layer of security compared to using just an API key.
For more details, refer to the Authentication Strategies Guide.
