[Feature Request] Provide WorkflowInfo.initiator?

[lorensr]

If this is helpful to users, we could expose startWorkflow.continueInitiator as WorkflowInfo.more.initiator: Initiator. Currently we're not, but I'm opening this issue to see if there are any user requests / use cases for it.

export enum Initiator {
  Unspecified = 0,
  ContinueAsNew = 1,
  Retry = 2,
  Cron = 3,
}

One possible use case is determining whether the current Execution was initiated due to retry vs continue as new.