feat(llm): 处理完成的消息自动软删除并隐藏删除按钮

- MarkAsProcessed 在写入 reply/processed_at 的同时设置 deleted_at，
  避免 /admin/llm 队列页堆积已处理消息（仍可勾选"包含已删除"查看）
- 前端列表中已删除的消息行隐藏删除按钮，改为显示灰色"已删除"标签

Co-Authored-By: Claude <noreply@anthropic.com>

internal/autoreply/queue.go

@@ -92,13 +92,15 @@ func (q *DBMessageQueue) MarkAsProcessing(id uint64) error {
 	return q.db.Model(&llmMessageQueueRecord{}).Where("id = ?", id).Update("status", statusProcessing).Error
 }
 
-// MarkAsProcessed marks a message as successfully processed
+// MarkAsProcessed marks a message as successfully processed and soft-deletes it
+// 处理完成的消息直接软删除，避免队列页堆积；保留 reply/processed_at 便于查询历史
 func (q *DBMessageQueue) MarkAsProcessed(id uint64, reply string) error {
 	now := time.Now()
 	return q.db.Model(&llmMessageQueueRecord{}).Where("id = ?", id).Updates(map[string]any{
 		"status":       statusProcessed,
 		"reply":        reply,
 		"processed_at": &now,
+		"deleted_at":   &now,
 	}).Error
 }
 

meshmap_frontend/src/components/AdminLLM.vue

@@ -298,9 +298,14 @@ onMounted(() => {
           <td>{{ formatTime(msg.received_at) }}</td>
           <td>{{ formatTime(msg.processed_at) }}</td>
           <td>
-            <button class="admin-button admin-button-small admin-button-danger" @click="handleDeleteMessage(msg.id)">
+            <button
+              v-if="!msg.deleted_at"
+              class="admin-button admin-button-small admin-button-danger"
+              @click="handleDeleteMessage(msg.id)"
+            >
               删除
             </button>
+            <span v-else class="muted-tag">已删除</span>
           </td>
         </tr>
         <tr v-if="messages.length === 0">
@@ -678,6 +683,15 @@ onMounted(() => {
   border: 1px solid transparent;
 }
 
+.muted-tag {
+  display: inline-block;
+  padding: 0.25rem 0.6rem;
+  border-radius: 6px;
+  font-size: 0.75rem;
+  color: #94a3b8;
+  background: #f1f5f9;
+}
+
 .status-badge[style*='#fff3cd'] {
   background: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%) !important;
   color: #92400e;