重构: 后端 df-ai/commands 拆分+df-nodes/workflow 改造+P0 bug 修复

- df-ai: context 历史中毒三档自愈 sanitize_messages(AC3)+anthropic_compat tool_use_id None 跳过(AC1/AC2)+删 router/stream 死码
- df-core: events 加 select_type+decisions 多选审批契约(F-260615-01)
- df-execute: shell run_command 工具复用(F-260615-05)
- df-nodes: human_node 多选校验+2 端到端测(F-01)+取消跳 set_failed(B-03b-R1/R2/R8)
- df-workflow: executor/dag/state cancel 闭环(B-06/07/03a/b)+provider approve options(R-PD-5)
- df-storage: find_path_conflict 抽公共(R-PD-11)+COLS 常量断言
- df-ideas: 删 IdeaPromoter/PromotionPolicy 死码(R-PD-14)
- src-tauri/commands/ai: secret keyring 迁移(FR-S1/R-PD-4)+GeneratingGuard RAII+disarm(B-09/26)+newConversation 软复位(B-10)+stream 心跳/stop select/空回复判错(B-02/04/05/15)+run_command(F-05)+mask audit(AR-3)
- src-tauri/commands/{project,task,workflow,mod,lib,state}: task detail IPC(F-02)+approve decisions+task list 联动(B-29)
- Cargo.lock+Cargo.toml 依赖同步

src-tauri/src/commands/task.rs

@@ -3,7 +3,7 @@
 use serde::Deserialize;
 use tauri::State;
 
-use df_core::types::new_id;
+use df_core::types::{new_id, TaskStatus};
 use df_storage::models::TaskRecord;
 
 use crate::state::AppState;
@@ -40,6 +40,20 @@ pub async fn list_tasks(
     result.map_err(|e| e.to_string())
 }
 
+/// 按 id 查任务，找不到返回 Err(供前端详情页)
+#[tauri::command]
+pub async fn get_task_by_id(
+    state: State<'_, AppState>,
+    id: String,
+) -> Result<TaskRecord, String> {
+    state
+        .tasks
+        .get_by_id(&id)
+        .await
+        .map_err(|e| e.to_string())?
+        .ok_or_else(|| format!("任务 {} 不存在", id))
+}
+
 /// 创建任务，返回完整记录
 #[tauri::command]
 pub async fn create_task(
@@ -69,7 +83,7 @@ pub async fn create_task(
     Ok(record)
 }
 
-/// 更新任务单个字段（字段名走 df-storage 白名单校验）
+/// 更新任务单个字段（字段名走 df-storage 白名单校验；status 值走枚举校验）
 #[tauri::command]
 pub async fn update_task(
     state: State<'_, AppState>,
@@ -77,6 +91,15 @@ pub async fn update_task(
     field: String,
     value: String,
 ) -> Result<bool, String> {
+    // 字段名注入由 df-storage 白名单兜底；这里补 status 值校验，
+    // 拦截拼写错误（in-progess / "in progress" / 大小写错等）静默落库。
+    if field == "status" && !TaskStatus::is_valid(&value) {
+        return Err(format!(
+            "非法 status 值 {:?}，合法值: {:?}",
+            value,
+            TaskStatus::valid_values()
+        ));
+    }
     state
         .tasks
         .update_field(&id, &field, &value)