- In `start_session`: increment `flow.usage_count` and set `flow.last_matched_at` when a flow is matched to a new session; errors are caught without blocking - In `resolve_session`: recalculate `flow.success_rate` as (resolved / total) across all sessions ever matched to the flow after each resolution; errors are caught without blocking the session close Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>