Provide an event watcher

[amimart]

Provide a way to react to some dataverse events

Context

Some components must be active regarding the state of the dataverse, especially when OrchestrationServiceExecutionOrderCredential are registered, these encapsulate the intent to trigger an execution, the concerned service shall react to fulfil this order.

Details

For a component to react on-chain events, a watching mechanism should allow it, I propose to implement a Waker who will ensure a provided function is triggered when a specific event occur.

The watching of such events could be implemented through the comet web socket, however this should be considered as critical and the implementation shall ensure that no events will be missed.