修复: 消息溯源P2切读确认完成 + 走查报告高优项

- P2 切读方案文档更新(确认批次B已上线)
- query LIKE 通配符转义(project/idea/task/knowledge 4 repo)
- dag.rs deep_merge null 覆盖全局配置
- dag.rs 通配 match 展开显式变体
- INDEX.md 补漏 10 个文档索引
- ARCHITECTURE.md 删除与新文档逐字重复
- coordinator.rs 加 #[deprecated] 编译守卫
- AiChat.vue 空值传播加 console.warn

src/components/AiChat.vue

@@ -237,6 +237,7 @@ function scrollToFirstPending(): void {
 const { confirmState, confirmDialog, answerConfirm } = useConfirm()
 async function confirmDeleteConversation(id: string) {
   const conv = store.state.conversations.find(c => c.id === id)
+  if (!conv) console.warn('confirmDeleteConversation: conv not found, id=', id)
   const title = conv?.title || t('aiChat.newConversation')
   // UX-260617-24:删除当前活跃对话加醒目提示(通用文案不区分,活跃对话误删影响更大)。
   const isActive = id === store.state.activeConversationId