Expand description
Session-id capture and hydration state machine for SubprocessController.
Two independent sources can set inner.session_id:
hydrate_session_id_from_config: best-effort seed from the picker “My Agents” reattach path (config-supplied, may be stale).record_captured_session_id[_inner]: authoritative capture from the CLI’s own stdout init event — always wins, and always overwrites a prior hydrated value.