Timeline-log now writes completed events to weekly rollup files at
~/.gstack/activity/activity-YYYY-WNN.jsonl. Wintermute answering
"what did I ship this week" reads one file, not 6 months of history.
Only completed events go to the activity index (not started events).
Old weeks are immutable. ls ~/.gstack/activity/ gives the full timeline.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>