Live-to-Final: prove historical hydration and fence terminal retry ownership (#6451)

* test: add historical hydration lifecycle proof

* fix: retry anchor persistence after terminal app errors

* fix: fence deferred anchor settlement ownership

* test: cover deferred anchor retry ownership

* fix: preserve terminal anchor retry across refresh

* fix: bind terminal anchor retry to turn owner

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Co-authored-by: Frank Song <franksong2702@gmail.com>

tests/test_stable_assistant_turn_anchor_registry.py

@@ -866,7 +866,7 @@ function _projectLiveAnchorActivityScene(){{
 }}
 function _completeSettledAnchorSceneForTurn(messages,index,scene){{ return scene; }}
 function _persistSettledAnchorScene(){{ persisted+=1; }}
-function _attachProjectedAnchorSceneToLastAssistant(messages){{{attach_scene}}}
+function _attachProjectedAnchorSceneToLastAssistant(messages,targetMessage=null,targetIndex=null){{{attach_scene}}}
 const messages=[{{role:'assistant',content:'final answer'}}];
 const renderedWorklog=_attachProjectedAnchorSceneToLastAssistant(messages);
 console.log(JSON.stringify({{