工具系统重构与定时任务管理

1. 工具抽象体系
   - 新增 Tool trait + ToolRegistry 注册表
   - 三种工具类型：ApiTool / StdioTool / ShellTool
   - 全局 REGISTRY (LazyLock) 作为主入口
   - BuiltinRegistry 简化为兼容层

2. 定时任务管理工具
   - 新增 manage_scheduled_tasks 工具（ApiTool）
   - 支持 list/add/update/delete/toggle 五种操作
   - 通过 LazyLock 延迟初始化数据库连接池

3. 定时任务分流
   - 新增 task_type 字段（model / system）
   - 模型可自由管理 model 任务
   - system 任务只读，修改操作被拒绝

4. CLI 支持
   - 新增 ias task 子命令（list/add/update/delete/toggle）

5. 清理
   - 删除废弃的 ias-auth 独立二进制
   - SkillResult 增加 Deserialize derive
   - 所有调用点更新为 crate::tools::xxx 新入口

src/db/models.rs

@@ -243,3 +243,163 @@ pub async fn load_summaries(pool: &PgPool, user_id: &str, limit: i64) -> Result<
     .map_err(|e| format!("查询摘要失败: {}", e))?;
     Ok(rows.into_iter().map(|(t,)| t).collect())
 }
+
+// ─── 定时任务 ───
+
+#[derive(Debug, Clone, sqlx::FromRow, Serialize, Deserialize)]
+pub struct ScheduledTask {
+    pub id: uuid::Uuid,
+    pub name: String,
+    pub description: String,
+    pub user_id: Option<String>,
+    pub command: String,
+    pub shell: String,
+    pub cwd: String,
+    pub interval_seconds: i32,
+    pub enabled: bool,
+    pub next_run_at: DateTime<Utc>,
+    pub last_run_at: Option<DateTime<Utc>>,
+    pub last_status: Option<String>,
+    pub task_type: String,
+    pub created_at: DateTime<Utc>,
+    pub updated_at: DateTime<Utc>,
+}
+
+/// 列出所有定时任务
+pub async fn list_scheduled_tasks(pool: &PgPool) -> Result<Vec<ScheduledTask>, String> {
+    let tasks = sqlx::query_as::<_, ScheduledTask>(
+        r#"
+        SELECT id, name, description, user_id, command, shell, cwd,
+               interval_seconds, enabled, next_run_at, last_run_at,
+               last_status, task_type, created_at, updated_at
+        FROM scheduled_tasks
+        ORDER BY next_run_at ASC
+        "#,
+    )
+    .fetch_all(pool)
+    .await
+    .map_err(|e| format!("查询定时任务失败: {}", e))?;
+    Ok(tasks)
+}
+
+/// 添加定时任务
+pub async fn add_scheduled_task(
+    pool: &PgPool,
+    name: &str,
+    user_id: &str,
+    command: &str,
+    interval_seconds: i32,
+    description: &str,
+    shell: &str,
+    cwd: &str,
+    task_type: &str,
+) -> Result<uuid::Uuid, String> {
+    let id = uuid::Uuid::new_v4();
+    sqlx::query(
+        r#"
+        INSERT INTO scheduled_tasks (id, name, description, user_id, command, shell, cwd, interval_seconds, task_type)
+        VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9)
+        "#,
+    )
+    .bind(id)
+    .bind(name)
+    .bind(description)
+    .bind(user_id)
+    .bind(command)
+    .bind(shell)
+    .bind(cwd)
+    .bind(interval_seconds)
+    .bind(task_type)
+    .execute(pool)
+    .await
+    .map_err(|e| format!("添加定时任务失败: {}", e))?;
+    Ok(id)
+}
+
+/// 更新定时任务（只更新非 None 的字段）
+pub async fn update_scheduled_task(
+    pool: &PgPool,
+    id: &uuid::Uuid,
+    name: Option<&str>,
+    command: Option<&str>,
+    interval_seconds: Option<i32>,
+    description: Option<&str>,
+    shell: Option<&str>,
+    cwd: Option<&str>,
+) -> Result<bool, String> {
+    let mut sets = Vec::new();
+    let mut idx = 1u32;
+
+    if name.is_some() {
+        sets.push(format!("name = ${}", idx)); idx += 1;
+    }
+    if command.is_some() {
+        sets.push(format!("command = ${}", idx)); idx += 1;
+    }
+    if interval_seconds.is_some() {
+        sets.push(format!("interval_seconds = ${}", idx)); idx += 1;
+    }
+    if description.is_some() {
+        sets.push(format!("description = ${}", idx)); idx += 1;
+    }
+    if shell.is_some() {
+        sets.push(format!("shell = ${}", idx)); idx += 1;
+    }
+    if cwd.is_some() {
+        sets.push(format!("cwd = ${}", idx)); idx += 1;
+    }
+
+    if sets.is_empty() {
+        return Ok(false);
+    }
+
+    sets.push("updated_at = NOW()".to_string());
+
+    let sql = format!(
+        "UPDATE scheduled_tasks SET {} WHERE id = ${}",
+        sets.join(", "),
+        idx
+    );
+
+    let mut query = sqlx::query(&sql).bind(id);
+
+    if let Some(v) = name { query = query.bind(v); }
+    if let Some(v) = command { query = query.bind(v); }
+    if let Some(v) = interval_seconds { query = query.bind(v); }
+    if let Some(v) = description { query = query.bind(v); }
+    if let Some(v) = shell { query = query.bind(v); }
+    if let Some(v) = cwd { query = query.bind(v); }
+
+    let rows = query
+        .execute(pool)
+        .await
+        .map_err(|e| format!("更新定时任务失败: {}", e))?;
+
+    Ok(rows.rows_affected() > 0)
+}
+
+/// 删除定时任务
+pub async fn delete_scheduled_task(pool: &PgPool, id: &uuid::Uuid) -> Result<bool, String> {
+    let rows = sqlx::query("DELETE FROM scheduled_tasks WHERE id = $1")
+        .bind(id)
+        .execute(pool)
+        .await
+        .map_err(|e| format!("删除定时任务失败: {}", e))?;
+    Ok(rows.rows_affected() > 0)
+}
+
+/// 切换定时任务启用状态
+pub async fn toggle_scheduled_task(pool: &PgPool, id: &uuid::Uuid) -> Result<(bool, bool), String> {
+    let row = sqlx::query_as::<_, (bool,)>(
+        "UPDATE scheduled_tasks SET enabled = NOT enabled, updated_at = NOW() WHERE id = $1 RETURNING enabled",
+    )
+    .bind(id)
+    .fetch_optional(pool)
+    .await
+    .map_err(|e| format!("切换定时任务状态失败: {}", e))?;
+
+    match row {
+        Some((enabled,)) => Ok((true, enabled)),
+        None => Ok((false, false)),
+    }
+}