feat: add one-turn situation graph update UI

components/situation-graph-view.jsx

@@ -55,6 +55,11 @@ export default function SituationGraphView({
 }) {
   if (!situationGraph) return null;
 
+  const selectedQuestionText =
+    typeof selectedQuestion === "string"
+      ? selectedQuestion
+      : selectedQuestion?.question ?? null;
+
   const activeUnknown = situationGraph.activeUnknownNodeId
     ? situationGraph.nodes.find((node) => node.id === situationGraph.activeUnknownNodeId)
     : null;
@@ -67,10 +72,10 @@ export default function SituationGraphView({
 
   return (
     <div className="space-y-4">
-      {selectedQuestion?.question && (
+      {selectedQuestionText && (
         <section className="rounded-lg border-2 border-green-300 bg-green-50 p-5">
           <h2 className="mb-2 text-base font-bold text-green-800">Selected Question</h2>
-          <p className="text-base font-medium text-gray-900">{selectedQuestion.question}</p>
+          <p className="text-base font-medium text-gray-900">{selectedQuestionText}</p>
         </section>
       )}