Branching out parallel subtasks into separate processes

[b78]

For complex workflows, I often want to branch out multiple subtasks into separate processes, e.g. documenting files - I want to run documentation workflows on many files in parallel. Or fixing multiple smaller todos in separate subtasks.

It would be amazing if orchestrator mode could spawn asynchronous subtasks, that also get their own terminal access to avoid competition.

This probably needs a file locking mechanism though, where we analyze which files the tools and commands are likely working on and lock them.