[amp-player]: Add error handling events

## Describe the new feature or change to an existing feature you'd like to see
- With the new proposal to programatically control the amp-player, it would be helpful to add error events to the player.
- If there's any error that is emitted, e.g. render timeouts, it should fire an event that can be listened to just in case it cannot resolve that error.

## Describe alternatives you've considered
- Currently there are no error events and the only way is to reload the page.

## Additional context
- An example of an error event
- Ref [#28416](https://github.com/ampproject/amphtml/issues/28416)

cc @Enriqe