fix(rectification): stop speaking unstampable distinguish stems (BUG-674/675)

Distinguish followups that cannot stamp a probe now go to persistExhaustionCollect instead of repeating the card stem in the assistant body. Choice focuses without asked_turn_id hang on the last assistant turn, and persisted_question with a live choice_card renders the existing card. Representative-time inconsistency is warn-only (BUG-676 investigating).

frontend/tests/rectification-surface-state.test.ts

@@ -16,6 +16,7 @@ import {
   rectificationQuestionRetryActive,
   interviewCollectWaiting,
   interviewChoiceCardUnavailable,
+  persistedQuestionSurface,
   interviewStopReasonFromSnapshot,
   RECTIFICATION_COLLECT_WAITING_PLACEHOLDER,
   rectificationReadonlyRangeCopy,
@@ -111,6 +112,17 @@ test("question gap: nothing is shown while busy, readonly, regenerating, or for
   assert.equal(rectificationQuestionGapState({ ...gapBase, resumableCase: false }), "idle");
 });
 
+test("a persisted choice with a live card is not the spoken-only prompt surface", () => {
+  assert.equal(
+    persistedQuestionSurface({
+      questionKind: "choice",
+      hasChoiceCard: true,
+      questionPersisted: true,
+    }),
+    "choice_card",
+  );
+});
+
 test("question gap: a persisted focus question is shown instead of preparing", () => {
   assert.equal(
     rectificationQuestionGapState({ ...gapBase, questionMissing: false, questionPersisted: true }),