Add human-led conversation learning loop

docs/architecture.md

@@ -144,3 +144,6 @@ docs/                          Maintainer and agent documentation
 ## Known design pressure
 
 `src/bootstrap.ts` remains a large composition root and the legacy single-runtime path duplicates parts of the multi-account delivery flow. Changes should reduce duplication through small factories/policies without hiding operational state or merging account-owned dependencies into process-global singletons.
+### Learning is derived and revocable
+
+Raw Matrix history remains authoritative. Event attribution, trajectories, decisions, retrieval selections, and evaluation runs are separate projections so attribution fixes and later safety outcomes can revoke examples without rewriting chat history. The retrieval provider is a local interface rather than a dependency on a hosted observability framework; external tools can consume the audit/evaluation seam later without becoming runtime infrastructure.