Why: the product conversation path needs the intent journal and recovery pairing, but making the transcript the authoritative context would freeze the assembled system prefix (memory/plans/injections go stale). JournalOnly keeps the session as journal-only: recovery runs against it, the context always comes from History, and the recovered outcomes are injected as a system note. Separately, the one-time History seed was memory-only and silently lost from the second run on (authority mode); it is now persisted except in JournalOnly mode. Evidence: GOWORK=off go vet + go test -count=1 ./... green; TestJournalOnlyRecoversWithoutTranscriptAuthority (journal gets the replayed pair exactly once, history never enters the journal, the recovery note precedes the new user message, seeds stay out); persistedProjection honors JournalOnly; all pre-existing durable and harness tests pass unchanged (default semantics untouched). Impact: new opt-in Config.JournalOnly; default (false) behavior is byte-identical. Refs: Agent-System-Documents#43 (N3 plan WP2)