Delete run manifest domain model

docs/internal/manifest.md

@@ -2,8 +2,8 @@
 
 ## Purpose
 
-Explain the session-progress and invocation-audit models implemented by
-`internal/manifest`. Physical manifest placement belongs in
+Explain the session-progress model implemented by `internal/manifest`. Physical
+manifest placement belongs in
 [Operations](../operations.md#local-state-layout).
 
 ## Session Manifest
@@ -143,7 +143,7 @@ establish a current immutable snapshot.
 
 `manifest.LocalStore`:
 
-- accepts only the exact supported schema version for each manifest kind;
+- accepts only the exact supported session-manifest schema version;
 - validates stage-map identity without synthesizing missing maps, records, or
   names;
 - retains only representation-preserving collection normalization;