Inbound Stream Status

The <Stream> verb's own statusCallbackUrl (build task's XML shape): Plivo posts stream-lifecycle events here (started/stopped/ errored) separately from the call-level webhooks above. Signature-gated the same open-when-unconfigured way as every other inbound route in this module.

⛔"started" IS THE ONE EVENT THIS ROUTE ACTS ON, because it is the first moment a caller can be told apart from one still ringing in the hold queue. An inbound row is 'ringing' from /inbound/answer until hangup, and nothing used to transition it when the media stream connected -- which means the hold queue (inbound + 'ringing' + under 30 minutes, service.list_calls) reads every live Rooster conversation as a caller on hold, and the desk's Answer button (answer_here) would redirect somebody mid-sentence onto hold music and then the desk. Every other event (stopped/errored) is still only logged: the voice_calls row is already the record of what actually happened to the call (recording/DTMF/callback fields), and a redundant status ledger would be a second place to look for the same fact.