Add a way to identify reject handlers for use by Transponders to reject Promises

[eudaimos]

It would be useful if when using a Transponder to generate a Promise from a setCtx or setAppCtx call, a set of filtered trigrams could be used to identify when the promise should be rejected.

This is useful for clients working with the network that are still promise-based implementations and wish to use promise rejection as a status that things went wrong and act accordingly.

[eudaimos]

Possible implementation might be the Transponder adding handlers to the wrapped Network and then use the reject function if those are called.

Would this require decorating a handler with metadata that can be used in-stream like how the control works to allow the network to manage messages?