Feature Request: limit automated delivery of insulin

[marionbarker]

Is your feature request related to a problem? Please describe.
Some people, with errors in the reported CGM values, have reported excessive automated delivery of insulin.

Describe the solution you'd like
A safety feature could be added to Loop to prevent automated delivery above a given IOB.

Describe alternatives you've considered
I'm sure there are alternatives, this is the one that comes to mind. I think it's an important safety feature.

Additional context
See this zulipchat discussion link: https://loop.zulipchat.com/#narrow/stream/148543-Loop/topic/Maximum.20IOB/near/161028798

[github-actions]

This issue is stale because it has been open for 30 days with no activity.

[marionbarker]

Closing this. It was addressed with #1871.
See also #1894