Checkpoint peering identity and opt-in discovery

docs/architecture.md

@@ -15,6 +15,8 @@ Related documents:
 - [resilience.md](resilience.md): supervision, recovery limits and incidents.
 - [compose-deployment.md](compose-deployment.md): local/VM deployment and release workflow.
 - [settings-navigation.md](settings-navigation.md): User/Admin workspace, scraper tabs and deep links.
+- [peering.md](peering.md): optional private server-to-server catalog and transfer.
+- [discovery.md](discovery.md): reader-owned, opt-in deterministic discovery feed and its limits.
 
 ## 1. Principles