WIP branch: https://github.com/OpenCoven/coven-code/tree/wip/post-pr175-stream-query-hardening Follow-up scope: - preserve tool-start input/incomplete JSON - explicit terminal events - cancellation drain - usage accounting - unique attempt UUIDs - indexed text/thinking/tool/EOF/error tests
WIP branch: https://github.com/OpenCoven/coven-code/tree/wip/post-pr175-stream-query-hardening
Follow-up scope: