Tabs and multitasking

[aleksei-myor]

It would be very convenient to have tabs for unrelated tasks/threads with different contexts in one VS Code project. Especially, when the project is large and we need to handle a few tasks in parallel. Current solution causes additional actions like resume tasks that consume extra tokens, and task/subtask relations always get broken on tasks switching, so I avoid switching unless really necessary. Tabs would solve it.

[EHMilon]

#1853

[kevinvandijk]

Thanks @aleksei-myor. Closing as duplicate of #1853 but any additional comments are very welcome there!