Improve in-app guidance on configuring automation rules

[nathanielrindlaub]

I think we should provide more tips and in-app guidance in the AddAutomationRuleForm.jsx component. For example:

• [ ] rename "run inference" trigger to "request ML prediction"
• [ ] prevent users from prevent users from using an “on-image-added” trigger if their selected model is a classifier/expects crops. This would entail adding an expectsCrops: <boolean> field to the MLModel schema so we have something to check, and if true, force users to choose on-label-added and provide and explanation as to why