[Bug]: 执行中的任务，点了停止后显示上停止了，但实际依然在执行

## QwenPaw Version

2.2 web

## Description

我输入了一个指令，发现有误就点了停止，我绝对确认对话框下方的执行中的那个□消失了、变成了正常的↑（因而我输入了修正后的指令，他就抛出了409报错），但我刷新页面时发现他依然在执行、事实上还在执行有误的指令。

## Logs / Screenshots

The report concerns QwenPaw 2.2 web: reproduce a running task, stop it, submit a corrected instruction, and refresh to verify whether the original task still runs. Trace the stop action and running-state transition from the web interface through task execution; done means stopping actually terminates the original task, the UI remains accurate after refresh, and the corrected instruction no longer gets a 409 caused by it.

Scritto dal modello di indicizzazione a partire dal testo della issue.