[szweibel]

Summary

• add an app-owned SQLite compaction overlay while preserving the canonical AIChatAgent transcript, files, UI history, and exports
• compact only complete settled turns, retaining the first complete turn plus the three most recent turns with tool and reasoning groups intact
• use 80%/60% high-water and target-water hysteresis, capped by explicit system, tool, and output reserves
• preserve exact server-validated panel-scope provenance and invalidate stale overlays with a content fingerprint
• keep summaries chronological, bounded, non-system-role, and free of raw reasoning; retain the prior overlay if compaction fails

Verification

• bun run check
  • backend: 464 passed
  • frontend: 282 passed
  • tooling: 22 passed
  • production build and Wrangler staging dry run passed
• actual local Worker lifecycle smoke passed and deleted its synthetic workspace
• browser acceptance passed: canvas persistence, file bytes, export/import, gallery lifecycle, preview isolation, reload, and UI cleanup

No deployment is included.