allow run custom commands when VSCode is closed

[zhangtao-git]

I use this plugin to do some automated tasks, which is really great.
But I am now encountering some problems. I expect that when VSCode is closed, some interfaces similar to "commands" can also be opened to perform the closing and cleaning work of tasks.
The problem I encounter is: I use this plugin to execute some continuous tasks, such as "tsc --watch". In order to reuse these tasks, I create a file globally to record the information of the task project. Once VSCode is restarted or closed, the tasks will be automatically closed, but the global file that records the task information is still there. It would be great if a custom instruction could be executed to clean up the tasks when VSCode is closed.