fix(confidence-engine): avoid Done result shadowing

components/scenario-form.jsx

@@ -365,7 +365,7 @@ export default function ScenarioForm() {
     doneInProgressRef.current = true;
 
     try {
-      const result = await executeEpisodeDone({
+      const doneResult = await executeEpisodeDone({
         resultSituationGraph: result?.situationGraph,
         targetNodeId,
         focusedContributions: focusedContributions ?? [],
@@ -381,8 +381,8 @@ export default function ScenarioForm() {
       });
 
       /* CU synthesis — install only on success */
-      if (result?.synthesisResult?.ok && result.synthesisResult.data?.currentUnderstanding) {
-        setCurrentUnderstanding(result.synthesisResult.data.currentUnderstanding);
+      if (doneResult?.synthesisResult?.ok && doneResult.synthesisResult.data?.currentUnderstanding) {
+        setCurrentUnderstanding(doneResult.synthesisResult.data.currentUnderstanding);
       }
       /* On synthesis failure: KEEP nextGraph, KEEP Findings, KEEP existing CU. Do NOT rollback. */