docs(plan): record live projection checkpoint

docs/plans/2026-07-21-gamewindow-slice-4-live-entity-integration.md

@@ -17,8 +17,11 @@ them inside a mechanical extraction.
   ownership. Landed in `d68c83d1`, `5882b308`, and `fcb66198`. The final
   exact-record host checkpoint passed three clean reviews plus 6,743 Release
   tests / 5 skipped on 2026-07-21.
-- [ ] B — pure appearance/projection helpers and controller-level
-  characterization tests.
+- [x] B — pure appearance/projection helpers and controller-level
+  characterization tests. Landed in `69a2ca0c`. Exact appearance/collision
+  replacement, default-pose resolution, local-shadow ownership, and recursive
+  retained projection withdrawal passed three clean reviews plus 6,799 Release
+  tests / 5 skipped on 2026-07-21.
 - [ ] C — hydration create/materialize/landblock-recovery ownership and direct
   CreateObject/streaming cutover.
 - [ ] D — ObjDesc/Parent/Pickup/ready/withdraw ownership and exact retained
@@ -245,6 +248,15 @@ one-line façades.
 - Run appearance, animation, spawn-adapter, collision, resource-lifecycle,
   and new characterization suites; full Release build/test; review cycle.
 
+Completed in `69a2ca0c`. The checkpoint also pinned the retail `add_child` /
+`set_parent` / `leave_world` boundary required by C and D: parent timestamps
+are staged before validation, accepted relationships are committed one at a
+time, and world withdrawal recursively removes the exact parent-first
+projection subtree while retaining logical identity and retry ownership.
+Release build completed with zero warnings and errors; 6,799 tests passed with
+five intentional skips; retail, architecture, and adversarial re-reviews were
+clean.
+
 ### C — create and materialization
 
 - Implement hydration CreateObject registration, first materialization,