Compose execution observers in order

docs/roadmap/implementation.md

@@ -462,7 +462,7 @@ remains covered by integration tests.
 
 ## Stage 7 — Expose Coordination Through The Facade
 
-**Status:** Complete; public tests await the observer composition wiring in Stage 9.
+**Status:** Complete; public coordinator tests passed with observer composition.
 
 **Scope:** public types, argument checks, and ordinary-execution adapters.
 
@@ -485,7 +485,7 @@ explicit observer-composition dependency forward, without an intermediate gate.
 
 ## Stage 8 — Verify Coordinator Capacity And Cancellation Boundaries
 
-**Status:** Complete; race validation awaits the observer composition wiring in Stage 9.
+**Status:** Complete; focused race validation passed with observer composition.
 
 **Scope:** the subtle assembled execution lifecycle.
 
@@ -510,6 +510,8 @@ contexts as failure guards, not timing-dependent synchronization.
 
 ## Stage 9 — Add Observer Composition
 
+**Status:** Complete.
+
 **Scope:** fan-out helper and final coordinator-observer wiring.
 
 1. Implement internal synchronous fan-out over a copied function slice and the