IsDocumentReadyAsync + Task.Delay pattern

[MarcinJuraszek]

There really needs to be some way to wait for a document to be ready, to replace the recommended "check if it's ready, and if not wait 2s and check again" pattern.

[dluc]

@MarcinJuraszek we're open to suggestions :-) It's usually either push or pull, and the service doesn't have a mechanism for pushing notifications. I'd love hearing ideas though, I'm sure I haven't thought too much about this.
Couple of raw thoughts on this topic:

• on large deployments, one might not care about waiting at all, just ingesting all the changes as they occur in real time, decoupling queries from the learning phase. E.g. when asking a person for an answer, that person might not be up to speed yet, and one might get a different answer if asked again later
• we hopefully can make ingestion fast, so fast that polling shouldn't be a problem. The quality of answers though will differ over time, considering that we plan to add a lot of background consolidation steps and synthesis, which can take hours.