- POST /discord/nodes/{id}/streams/stop: stream_id must be guild:channel
snowflakes, so a malformed id is a 422 instead of a Firestore path error.
- Offline footer said channels resume on reconnect; ad-hoc ones stop once
the node is gone past the lease grace (reconcile_once). Say so.
- Picker: say why Start is disabled when the node has no system.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>