Check context cancellation

Always implement proper cancellation mechanisms in concurrent code to prevent goroutine leaks and enable timely shutdown. Two key practices:

1. Add context checks at the beginning of loops in goroutines:

   for {
    // Honor caller cancellation to avoid goroutine leaks
    select {
    case <-ctx.Done():
        logger.Debug("operation cancelled")
        return
    default:
    }
       
    // Continue with operation that might block
    data, err := ReadMessage(conn)
    // ...
   }
   

2. Add context parameters to functions that may block for extended periods: ```go // Before func (impl *transporterImpl) Send(m msg.Message) error

// After func (impl *transporterImpl) Send(ctx context.Context, m msg.Message) error ```

This pattern allows callers to cancel operations when a user exits manually or when operations exceed timeouts, preventing resource leaks and ensuring responsive application behavior during shutdown.