Add callouts and make category fields readonly after creation

[ohltyler]

Signed-off-by: Tyler Ohlsen ohltyler@amazon.com

Description

This PR blocks users from editing the selected category fields after initial detector creation. The reason for this change is because the anomaly results and charts can get in weird states if the detector cardinality type is changed, and lead to showing confusing and/or misleading data to the users (e.g., making a single-category high-cardinality detector into a non-high-cardinality detector will show multiple results with the same timestamp for each entity).

Changes include:

• Adding callouts to the model config page describing the changes. In the creation flow, show a warning callout once the user initially enables the category field checkbox. In the edit flow, show an info callout describing why the category field selections (enabled or disabled, selected fields) are readonly.
• Making the checkbox and combo box readonly when editing the model config

Testing:

• Sanity tested the functionality for the create & edit flows
• Updated and added unit tests

Screenshots:

Warning callout in creation flow:

Info callout in edit flow:

Check List

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[ohltyler]

Everything is approved by UX, only waiting on wording confirmation. In the meantime everything else is ready for review.