Phase 7 — Logs, memory, and the echo

Session logs and recaps in the thread, history and stats, and then the **Google return path** — last because it is the only loopable edge in the system. Echo-loop prevention is the app's job, via the content fingerprint stored since phase 1.

## In order
1. #46 — Session logs and recaps in the thread
1. #47 — History and stats
1. #48 — Google return path — events.watch, renewal, nightly reconcile, echo-loop prevention
1. #49 — Verify events.watch max TTL and privateExtendedProperty AND/OR

Start by reading the four referenced work items, #46 through #49, in their listed order; the issue names no files, tests, or entry points. Done means session logs and recaps, history and stats, the Google return path with renewal and nightly reconciliation, echo-loop prevention, and verification of events.watch TTL and privateExtendedProperty behavior are all covered.

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