voice-post-call — Post-session transcript + summary handling

Convention: see gbrain's skills/conventions/quality.md for citation rules + back-link enforcement, and skills/_brain-filing-rules.md for the filing decision protocol. (These are not copied by the install; the relative paths resolve only if your host repo mirrors gbrain's skills layout.)

Iron Law

Every call gets processed, even on tool-call failure. The voice persona MAY log mid-session via an opted-in write tool, OR the call may end without that tool firing (model forgot, WebRTC dropped, browser crashed). A call-end handler should post a structured signal regardless so the brain still gets the transcript + audio reference — see "Two firing paths" below for which of these ships today and which the operator implements.

If both paths fire (the tool call AND the call-end handler), the second one is idempotent — it sees the brain page already exists and updates instead of duplicating.

The pipeline

1. CAPTURE  → MediaRecorder on the host repo's voice-agent service captures
              the full call audio (webm/opus) to /tmp/calls/<ts>-<persona>.webm.
              The browser client at /call?te…