feat(timeline): 事件时间轴支持删除视频会话

三端联动实现（fam-ui -> fam-core -> fam-edge），沿用项目里"NAS 转发写请求
到 Oracle"的既有模式（照抄 identity_correct 那套骨架）：

- fam-edge：oracle_db.py 新增 delete_video()（删 events+videos 行 + 磁盘上
  的运动片段文件；不清理 ss_motion_events 源事件，因为素材一旦处理完就不会
  被生产者重新捡起，删片段不会触发重新分割）；api_gateway.py 新增
  POST /api/oracle/video/delete
- fam-core：新增 db_layer.delete_sync_video()（第一个"NAS 直接写自己镜像表"
  的函数——增量同步只做 upsert 感知不到删除，不能像纠错那样靠 trigger_now()
  拉增量顺带清理）+ oracle_sync.push_video_delete() + ui_api.py 新增
  DELETE /api/ui/videos/<id>（先回推 Oracle，成功后才清本地镜像，避免数据
  不一致）
- fam-ui：Timeline.vue 详情卡片加删除按钮（原生 confirm() 二次确认，项目里
  之前没有确认弹窗组件先例）；api.js 新增 deleteVideo()

新增 6 个 delete_video 单元测试；已在 Oracle/NAS 用自造测试数据完整跑通端
到端链路（转发成功、两端记录清理、磁盘文件删除、幂等 404），未触碰任何真
实监控数据。

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

fam-ui/src/api.js

@@ -33,6 +33,7 @@ export const api = {
 
   videos: (params = {}) => request(`/api/ui/videos${qs(params)}`),
   videoDetail: (id) => request(`/api/ui/videos/${id}`),
+  deleteVideo: (id) => request(`/api/ui/videos/${id}`, { method: 'DELETE' }),
   stats: (date) => request(`/api/ui/stats${date ? '?date=' + date : ''}`),
   people: () => request('/api/ui/people'),
   peopleClips: (label, limit = 10) => request(`/api/ui/people/clips?label=${encodeURIComponent(label)}&limit=${limit}`),

fam-ui/src/views/Timeline.vue

@@ -94,6 +94,28 @@ const modelBadges = computed(() => {
   const provider = detail.value?.video?.compute_provider || ''
   return provider ? String(provider).split(',').map(p => p.trim()).filter(Boolean) : []
 })
+
+const deleteBusy = ref(false)
+const deleteError = ref('')
+
+async function deleteVideo(id) {
+  if (!confirm('确定删除这个视频会话吗？此操作不可恢复，会同时删除对应的视频文件。')) return
+  deleteBusy.value = true
+  deleteError.value = ''
+  try {
+    await api.deleteVideo(id)
+    videos.value = videos.value.filter(v => v.id !== id)
+    if (selectedId.value === id) {
+      selectedId.value = videos.value.length ? videos.value[0].id : null
+      if (!selectedId.value) detail.value = null
+    }
+    loadStats()
+  } catch (e) {
+    deleteError.value = e.message
+  } finally {
+    deleteBusy.value = false
+  }
+}
 </script>
 
 <template>
@@ -143,9 +165,14 @@ const modelBadges = computed(() => {
           <span>{{ detail.video.camera_name || '未知摄像头' }}</span>
           <Badge tone="ok">会话 #{{ detail.video.id }}</Badge>
           <Badge v-for="m in modelBadges" :key="m" tone="neutral">{{ m }}</Badge>
+          <button :disabled="deleteBusy" @click="deleteVideo(detail.video.id)"
+            class="ml-auto rounded-lg border border-danger/35 bg-danger/14 px-2.5 py-1 text-xs font-medium text-danger transition-colors hover:bg-danger/25 disabled:opacity-40">
+            {{ deleteBusy ? '删除中…' : '🗑 删除会话' }}
+          </button>
         </div>
         <div class="mt-1.5 font-mono text-[13px] text-text-dim tabular">⏱ {{ rangeStr }} · 文件 {{ detail.video.filename }}</div>
         <div class="mt-2.5 whitespace-pre-wrap text-sm leading-relaxed text-[#d6dce6]">{{ detail.video.summary_json || '暂无全局摘要' }}</div>
+        <div v-if="deleteError" class="mt-2.5 rounded-lg border border-danger/35 bg-danger/14 px-3 py-2 text-xs text-danger">{{ deleteError }}</div>
       </div>
 
       <EmptyState v-if="!detail.events.length" icon="🎞" text="该会话暂无时间点事件" />