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

crates/df-storage/src/crud/task_repo.rs

@@ -378,10 +378,11 @@ impl TaskRepo {
             }
             // keyword: title/description LIKE %kw%(P2,对齐知识库 search 的 LIKE 模式)
             if let Some(kw) = &keyword {
-                let pat = format!("%{kw}%");
+                let escaped = kw.replace('%', "\\%").replace('_', "\\_");
+                let pat = format!("%{escaped}%");
                 let p1 = params_vec.len() + 1;
                 let p2 = p1 + 1;
-                where_clauses.push(format!("(title LIKE ?{p1} OR description LIKE ?{p2})"));
+                where_clauses.push(format!("(title LIKE ?{p1} OR description LIKE ?{p2}) ESCAPE '\\'"));
                 params_vec.push(Box::new(pat.clone()));
                 params_vec.push(Box::new(pat));
             }