refactor(scheduler): move manual runs to console controls

docs/tools/scheduler.mdx

@@ -34,14 +34,17 @@ Create and manage scheduled tasks with natural language:
 - "Check server status every 2 hours"
 - "Remind me about the meeting tomorrow at 3 PM"
 - "Show all scheduled tasks"
-- "Run task a1b2c3d4 now"
 
-## Run an existing task now
+## Test-run an existing task
 
-Use `action="run"` with a task ID to queue an immediate test run. Manual
-execution works for disabled tasks and does not enable, delete, or reschedule
-the task. Its original `next_run_at` remains unchanged. A task cannot be run
-manually while the same task is already executing on schedule.
+Open the task in the authenticated Web console or Desktop app and click **Run
+now**. After you confirm the delivery, CowAgent queues one immediate execution
+to the task's configured channel and receiver. This user-initiated action is not
+exposed to the agent's scheduler tool.
+
+Manual execution works for disabled tasks and does not enable, delete, or
+reschedule the task. Its original `next_run_at` remains unchanged. A task cannot
+be run manually while the same task is already executing on schedule.
 
 <Frame>
   <img src="https://cdn.link-ai.tech/doc/20260202195402.png" width="800" />

docs/zh/tools/scheduler.mdx

@@ -34,11 +34,12 @@ description: 创建和管理定时任务
 - "每隔 2 小时检查一下服务器状态"
 - "明天下午 3 点提醒我开会"
 - "查看所有定时任务"
-- "立即执行任务 a1b2c3d4"
 
-## 立即执行已有任务
+## 测试执行已有任务
 
-使用任务 ID 调用 `action="run"`，可以排队进行一次即时测试执行。禁用状态的任务也可手动执行，且不会因此被启用、删除或重新调度，原有 `next_run_at` 保持不变。同一任务正在按计划执行时，不允许重复手动执行。
+在经过身份认证的 Web 控制台或 Desktop 应用中打开任务，点击 **立即执行**。确认发送后，CowAgent 会立即按任务已配置的通道和接收者执行一次。这个入口只允许用户手动触发，不会暴露给 Agent 的 scheduler tool。
+
+禁用状态的任务也可手动执行，且不会因此被启用、删除或重新调度，原有 `next_run_at` 保持不变。同一任务正在按计划执行时，不允许重复手动执行。
 
 <Frame>
   <img src="https://cdn.link-ai.tech/doc/20260202195402.png" width="800" />