新增: 待发箱抽屉与对话体验前端批

- 待发箱抽屉: ChatInput ⏰ 入口 + OutboxDrawer + useAiOutbox IPC 封装
- U2 进度语义三层: 内容层(最近动作) + 静默三档降速脉冲, 永不自动判死
- 流式心跳自愈: 竞态窗口旧任务迟到完成事件误收敛的自愈判定(949 前端兜底)
- 953 截断提示: 末条气泡渲染截断标记 + 继续输出按钮, 事件契约透传

src/components/ai/ChatInput.vue

@@ -66,6 +66,17 @@
       >
         <svg aria-hidden="true" width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M13 2H6a2 2 0 00-2 2v16a2 2 0 002 2h12a2 2 0 002-2V9z"/><polyline points="13 2 13 9 20 9"/></svg>
       </button>
+      <!-- 定时/待发箱入口(设计 2026-10-10 §3.4):icon-only ⏰ 开 OutboxDrawer
+           (组件内 Teleport 到 body,不占输入区布局;抽屉组件标签在模板尾部) -->
+      <button
+        type="button"
+        class="ai-img-pick-btn"
+        :title="$t('aiChat.outboxEntry')"
+        :aria-label="$t('aiChat.outboxEntry')"
+        @click="outboxOpen = true"
+      >
+        <svg aria-hidden="true" width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><circle cx="12" cy="12" r="10"/><polyline points="12 6 12 12 16 14"/></svg>
+      </button>
       <!-- L2 状态机停止按钮三态(批2 1c):conv_state 派生 generating/stopping/error 三态,
            idle(或 conv_state 未收到回退旧 streaming=false)显发送按钮。双轨过渡不强制全替旧 bool。 -->
       <button
@@ -119,6 +130,8 @@
       @dismiss="dismissEnrichment"
       @update:enrichment-expanded="enrichmentExpanded = $event"
     />
+    <!-- 定时/待发箱抽屉(⏰ 入口;Teleport 到 body 渲染,此处仅挂组件) -->
+    <OutboxDrawer :open="outboxOpen" @close="outboxOpen = false" />
     <div class="ai-input-hint">{{ $t('aiChat.inputHint') }}</div>
   </div>
 </template>
@@ -148,6 +161,7 @@ import SkillMention from './SkillMention.vue'
 import ImageInput from './ImageInput.vue'
 import MentionPopover from './MentionPopover.vue'
 import EnrichmentPanel from './EnrichmentPanel.vue'
+import OutboxDrawer from './OutboxDrawer.vue'
 import { taskApi } from '../../api/task'
 import type { AiMessage, ContentPart, SkillInfo, ProjectRecord, TaskRecord, IdeaRecord, MentionSpan } from '../../api/types'
 import type { MentionItem } from './MentionItem'
@@ -173,6 +187,8 @@ const { t } = useI18n()
 
 const inputText = ref('')
 const inputEl = ref<HTMLTextAreaElement>()
+// 定时/待发箱抽屉开合(⏰ 按钮开,抽屉 close 事件关;列表数据在 useAiOutbox 单例缓存)
+const outboxOpen = ref(false)
 
 // ── F-260614-05 Phase 2b: 图片输入(粘贴/拖拽/选择) ──
 // 待发送图片列表(url 或 base64 data URI + media_type),handleSend 时构造 ContentPart[]。