tower in tower setting for start_task_limit

[fosterseth]

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Feature Summary

Make a new start_task_limit tower in tower setting

We can build QA testing around this if it is a tower in tower setting, and we need QA testing because this feature could have serious downsides if not implemented correctly

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• [ ] UI
• [X] API
• [ ] Docs
• [ ] Collection
• [ ] CLI
• [ ] Other