Adapters support shutdown callback

[yjl9903]

Problem Statement

My adapter needs connect websocket to the remote server. Currently, adapter does not support custom shutdown or disconnect method, so I must manually invoke shutdown method of my adapter after bot.shutdown.

Proposed Solution

1. Add optional disconnect method to Adapter interface
2. Invoke all the adapters shutdown method in bot.shutdown

Alternatives Considered

No response

Use Case

// create bot
const bot = new Chat({ /* ... */ })

// do something

// shutdown
bot.shutdown()

// do not manually cleanup
// bot.getAdapter('...').disconnect()

Priority

None

Contribution

• I am willing to help implement this feature

Additional Context

No response