feat(socket): socket package

[samuelmasse]

Very basic example :

  const socket = new MessagingSocket({
    clientId: 'd0679b50-4c7d-4afe-a10b-fc98e06e318a'
  })

  socket.on('message', (message) => {
    console.log('Bot response :', message.payload.text)
  })

  await socket.connect()

  await socket.sendText('Hello there!')

Closes DEV-1610

[samuelmasse]

@laurentlp I think we should be good to merge this. This is still internal so we'll make improvements progressively.