feat: add voice session confirmation guardrails

frontend/src/views/VoiceStudio.vue

@@ -162,6 +162,13 @@ function formatDate(dateStr: string) {
   })
 }
 
+function formatConfidence(value: number | null | undefined) {
+  if (typeof value !== 'number') {
+    return 'n/a'
+  }
+  return `${Math.round(value * 100)}%`
+}
+
 function revokeRecordedAudioUrl() {
   if (recordedAudioUrl.value) {
     URL.revokeObjectURL(recordedAudioUrl.value)
@@ -718,6 +725,19 @@ onBeforeUnmount(() => {
 
             <div class="mt-6 grid grid-cols-1 gap-6 xl:grid-cols-[minmax(0,1.2fr)_minmax(0,0.8fr)]">
               <div class="space-y-6">
+                <div
+                  v-if="activeSession.latest_requires_confirmation"
+                  class="rounded-2xl border border-amber-200 bg-amber-50 p-4 text-amber-800"
+                >
+                  <div class="text-sm font-semibold">建议先确认这一轮理解</div>
+                  <p class="mt-2 text-sm">
+                    {{ activeSession.latest_confirmation_message || '系统对这一轮的理解还不够确定，建议家长先确认后再继续。' }}
+                  </p>
+                  <p v-if="activeSession.latest_understanding_summary" class="mt-2 text-xs text-amber-700">
+                    {{ activeSession.latest_understanding_summary }}
+                  </p>
+                </div>
+
                 <div class="rounded-2xl border border-gray-100 bg-white p-4">
                   <div class="flex items-center justify-between">
                     <h3 class="font-semibold text-gray-900">文本共创回合</h3>
@@ -839,6 +859,22 @@ onBeforeUnmount(() => {
                         <span class="font-medium text-gray-900">孩子：</span>
                         {{ turn.user_transcript || '暂无转写内容' }}
                       </div>
+                      <div v-if="turn.understanding_summary" class="mt-3 text-sm text-slate-600">
+                        {{ turn.understanding_summary }}
+                      </div>
+                      <div
+                        v-if="turn.requires_confirmation"
+                        class="mt-3 rounded-2xl border border-amber-200 bg-amber-50 px-3 py-3 text-sm text-amber-800"
+                      >
+                        <div class="font-medium">建议家长确认后再继续</div>
+                        <p class="mt-1">
+                          {{ turn.confirmation_message || '系统对这一轮的理解还不够确定，建议换一种说法再试一次。' }}
+                        </p>
+                        <p class="mt-2 text-xs text-amber-700">
+                          转写置信度：{{ formatConfidence(turn.transcript_confidence) }} ·
+                          意图置信度：{{ formatConfidence(turn.intent_confidence) }}
+                        </p>
+                      </div>
                       <div v-if="turn.user_audio_url" class="mt-3">
                         <audio class="w-full" :src="turn.user_audio_url" controls></audio>
                       </div>