Close quality and documentation workstream

docs/internal/overview.md

@@ -52,6 +52,13 @@ Narratio-level contracts; external transport and SDK details remain in
 adapters. The normative rules for these relationships remain in
 [Architecture](../policy/architecture.md).
 
+Command execution normalizes one private dependency value per invocation.
+Configuration reads, secret-directory reads, remote downloads, object-store
+construction, and restore phase functions use that value throughout the
+command. Public command entry points supply production defaults, while focused
+tests replace only the external or sequencing boundary they exercise without
+mutating package state.
+
 Pipeline execution and `session plan` share the same inclusive contiguous-range
 model and the same pure pre-execution decision over recorded status, force, and
 normalized resume validation. Planning applies that decision and modeled