Introduce `SyncEvent` channel in current stream management system, utilize to implement `SyncEventStream.EventStream` on translation shim type.

## Issue summary

- blocked by #4802
- Create `SyncEvent` channel in translation shim which captures `SyncEvent` instances.
- These are the events that should be emitted from the sync engine.

## Implementation details

- Calls to `EventStream` is essentially registering a subscriber to all `SyncEvents`.
- `SyncEvent` instances must be copied and sent to all subscribers

## Other information and links

-

## Acceptance criteria

[] `SyncEvent` subscribers should be able to subscribe to `SyncEvents` by calling `EventStream`.
[] 70% unit test coverage on introduced methods and functionality.